The birth of Monaco's Prince Albert and Princess Charlene's twins will be marked with a 42-cannon salute.
The royal couple are preparing to welcome their first children into the world in the coming weeks and have now shared how the happy news will be officially celebrated.
An official statement said: "On the occasion of the upcoming princely births. The Palace wishes to inform the people of Monaco and residents of the Principality of the following arrangements.
"In celebration of the joyous arrival of these two children, and without distinction, forty-two cannon shots (twenty-one for each child) shall be fired from the Fort Antoine and church bells shall ring for fifteen minutes, followed by boat horns."
An official proclamation signed by Albert will confirm the twins' birth and be displayed at the entrance to the Princely Palace, and at a later date the new arrivals will be presented in public.
The statement continued: "The date of the official introduction will be communicated at a later date/ The people of Monaco, residents and workers of the Principality as well as any individuals who wish to do so, are invited to attend the Princely Couple's presentation of Their children at the Place du Palais, in order to pay tribute to them and that day will be declared public holiday for all individuals working in Monaco in celebration of this time of great joy."
The message appealed for people to "put up bunting and flags, under the same provisions as on National Day" and asked for charitable donations to be made in lieu of gifts for the twins.

Stevi Ritchie wants to work for Simon Cowell now he has left 'The X Factor'.
The loveable singer was voted off the talent show on Sunday (23.11.14) after judges Mel B, Louis Walsh and Cheryl Fernandez-Versini decided to save Andrea Faustini, with only his mentor Simon opting so keep him in the competition.
Stevi is now hoping Simon - who he has become friends with - will find him a job in the music business, and insists he's up for doing anything.
When asked by 'This Morning' hosts Philip Schofield and Amanda Holden if he wanted to work for the music mogul, he said: "I'd love to in any way - whether that's working with Sarah-Jane Crawford or some part of 'X Factor' ... I don't know, something like what you guys are doing!"
Philip interrupted to ask: "So not singing then?"
To which Stevi replied: "I don't mind doing a bit of singing but I wouldn't mind doing what you guys are doing, because you're great."
Stevi also revealed Simon gave him some words of encouragement after the TV show went off air to lift his spirits.
He said: "I love him, he's so genuine and down to earth, and not only is he a mentor but he is a friend. I had a chat with him in the dressing room last night and it was really, really nice.
"I knew from day one that I wasn't going to win. It's one of those things. I just thought I just wanted to go as far as I can and bring the fun factor back. And I think I did that!"

Professor Green is up for competing on 'Strictly Come Dancing'.
The 30-year-old rapper insists the ballroom competition is one of the few celebrity-led TV show he'd consider appearing on, but is sure people would laugh at his limited dance skills.
Speaking at an exclusive gig at the Spotify offices in London to launch their new integration with Uber, he told BANG Showbiz: "It's probably the one thing I would do so people could laugh at me, and I could laugh at myself."
The 'Lullaby' rapper would be thrilled if he could master a few moves because it would make his wife Millie Mackintosh happy.
He said: "If I was even able to learn to dance a little bit, that'd be a bonus. I'm good at nodding my head, I know where the beat is, but my hands and feet just get confused."
Green - who released his third studio album, 'Growing Up In Public', in September - has not been avidly watching the popular Saturday night show this year, but praised BBC Radio 1 DJ Scott Mills, who was eliminated in week six, for trying his best.
He said: "Scott Mills did it, he put himself through the paces to do that! Hats off to Scott Mills, he really put everything into that, utmost respect for him for that."
Green personally picked up some fans in Uber cars to take them to his exclusive gig in London to celebrate the taxi company's partnership with Spotify.

Michelle Gomez has been given free food since starring in 'Doctor Who'.
The 47-year-old actress' appearance in the two-part series finale caused much excitement and controversy when it was revealed her character Missy was the Doctor's arch nemesis The Master regenerated into a female body.
Michelle has had a lot more attention since her starring role opposite Peter Capaldi - who plays the titular Time Lord - with the best fan encounter being with a 'Doctor Who' loving bakery worker in New York.
In an interview with GayTimes.co.uk, she laughed: "The other day I did get some croissants because there was a woman in Brooklyn that liked 'Doctor Who' so she gave me some free pastries ... I went in for a baguette and I went out with seven croissants!"
Michelle - who lives in NYC with her husband, 'Pirates of the Caribbean' star Jack Davenport, and their son Harry - is open to a return to the show but admits she doesn't know what showrunner Steven Moffat's plans are.
When asked to confirm if she was going to return to the BBC show, she said: "The thing is, is that you just can't tell can you? We just don't know ... There are no guarantees in life is there, really? Anyway the thing about being the Master of the universe is that I am in a parallel universe and yes means no and no means yes so it's always confusing as to, you know, what's really the truth. We don't know. We live in hope."

Ed Sheeran was "never really happy" with his image.
The 'Thinking Out Loud' star used to be overweight because of his poor eating habits and alcohol consumption but feels much better about himself after changing his diet.
He said: "I was never really happy with my image and then I realised it was because I was eating fried food and drinking beer every day. You don't have to kill yourself by getting into shape. Just eat right and don't drink every day."
The 23-year-old redhead admits he would still like to be healthier but doesn't enjoy working out in the gym so needs other exercise options.
He said: "I'd like to be healthier but I just don't enjoy working out. I enjoyed dancing and I lost weight while dancing. I could play football, I could do badminton. I just don't enjoy running on a treadmill or doing weights or doing sit-ups. It feels like it's quite a vain thing to do too much. I think if you do it for health reasons, then it's great but if you do it for image reasons, purely image reasons, I don't think it makes sense."
And the 'Drunk' hitmaker insisted he doesn't feel any pressure to look a certain way in his career.
Speaking to The Hits Radio for their 'State of Mind' campaign, he said: "There's enough fat people in the industry and there's enough skinny people in the industry and there's enough ginger people in the industry. There's enough everyone in the industry and usually the ones that aren't attractive are the ones that do the best"
Ed was talking to The Hits Radio for their 'State of Mind' campaign with charity YoungMinds, to help raise awareness for mental health issues suffered by today's youth. Listen to the show on 30 November at 10pm.

Liam Payne claims there were "divas" at the recording of the Band Aid 30 single.
The One Direction singer insists he and his bandmates - Harry Styles, Zayn Malik, Louis Tomlinson and Niall Horan - weren't in the studio for long enough to mingle with their fellow stars on the latest recording of 'Do They Know It's Christmas Time?' but says the charity track's organiser Bob Geldof "wasn't happy" with some of those who took part.
He told BBC Radio 1's Scott Mills: "We actually managed to get in the recording booth first so we were done in like an hour so we left. I missed all the drama.
"Bob did a little speech at the start. I say a little speech but it was the most epic thing I've ever heard in my life.
"He said to our manager, 'There are so many people here and you guys are the least fussed'. And I was like 'Yes. we're not divas. That's so good'."
"I'm not going to repeat the word he used to describe them but he wasn't happy with some people."
Liam's comments come after one of the singers on the track, Emeli Sande admitted she felt they should have recorded a different song to raise money to tackle the Ebola crisis in West Africa and apologised for causing offence with the lyrics.
She tweeted at the weekend: "Yes, I agree the lyric needs changing. In fact I feel a whole new song is required. Angelique Kidjo and I made and sang our own edits. Unfortunately, none of these made the final cut...
"I apologise if the lyrics of the song have caused offence. I wish the changes had been kept but that is out of my control. The sole objective is to raise awareness and money to provide medical aid to those suffering the Ebola outbreak, which is being worsened and amplified by poverty. Thank you so much for your support."
Meanwhile, Lily Allen has branded the project "smug" and said she would rather donate money directly than have taken part in the recording.
She said: "I got an email asking me to do it. It's difficult to explain why I didn't do it without sounding like a complete ****.
"I prefer to do my charitable bit by donating actual money and not being lumped in a with a bunch of people like that.
"It's like the success club and I'm not really in that club. I don't think I'm above it all - I'm way below it. But there's something a bit smug about it."

Brenton Thwaites will star in 'Pirates of the Caribbean: Dead Men Tell No Tales'.
The star will play the role of British soldier Henry, beating fellow actors such as Ansel Elgort of 'The Fault In Our Stars' and George MacKay from 'Pride', who are also said to have auditioned for the part.
The 25-year-old actor previously appeared in Australian soap 'Home & Away', but made his break into Hollywood blockbusters with the dark fantasy 'Maleficent' in which he starred as Prince Phillip.
Brenton will join Johnny Depp - who will once again reprise his swashbuckling character Captain Jack Sparrow for the fifth movie - and will be directed by duo Joachim Ronning and Espen Sandberg who worked together on 2012 adventure 'Kon-Tiki'.
The young actor will be hitting screens sooner than the July 2017 release date when he appears alongside Ewan McGregor in 'Son of a Gun' and in thriller 'The Signal', both due next year.
Meanwhile, Javier Bardem and Christopher Waltz are said to be in talks with the 'Pirates' producers to appear in the film - which has received scripting support from Jeff Nathanson - with the filmmakers also keen to bring back stars from the first film, 2003's 'Pirates of the Caribbean: The Curse of the Black Pearl'.
However, Keira Knightley who featured in the movie as Elizabeth Swann has ruled out a return to the franchise.
She told Digital Spy: "No, I don't think so.
"It was an amazing point in my life, but it was a good five-year chunk. It was incredible, but I can't really imagine going back to it."

Josh Hutcherson wants to "move on" from young adult films like 'The Hunger Games'.
The 22-year-old actor - who has starred in four films based on the dystopian 'Hunger Games' novels since 2011 - plans to explore other movie genres since filming has wrapped on the final installment of the franchise, which also stars Jennifer Lawrence and Liam Hemsworth.
When asked if he'd had enough of films marketed towards teenagers, Josh said: "I think I've done my fair share of that. It's been great, but it's time to move on."
The blonde actor -who has just finished filming for the drug themed 'Escobar: Paradise Lost', which is due to be released in cinemas from January 2015 - admitted that the Andrea Di Stefano directed film had subconsciously pushed him in another direction.
He told Empire magazine: "It wasn't like I was looking for anything specific to break away from Hunger Games, it just kind of happened. This film came along at the right time. I'm getting older so the roles are starting to skew older. It was never a conscious decision - time to play older! I did want to do something heavier, something more intense and when I read the script, this was it."
Josh - who has already executive produced two films - revealed that he isn't worried about his acting roles drying up because he would love to do more directing and producing.
He said: "I'm being patient, just reading a lot of scripts. I'm meeting with directors and producers, trying to build a foundation for my own directing and producing in the future."

Ryan Reynolds is "good" at changing diapers.
The 38-year-old actor and wife Blake Lively, 27, are expecting their first child together and the 'Green Lantern' hunk is looking forward to being a hands-on dad and isn't even concerned about the messier aspects of fatherhood.
He said: "I don't have a weak stomach. I'm good with diapers and diarrhoea and all that kind of stuff because I have lots of nieces and nephews, so I've done it all before."
Though the couple don't know whether they are expecting a boy or a girl, the 'Proposal' star is looking forward to having a little "buddy" to hang out with.
He said: "I'm just excited about having a buddy. We don't know if it's a boy or a girl yet, but whatever it is, you have this tether to reality that never goes away."
Though Ryan is excited about being a dad, he knows he needs to leave "room for error" as he won't do everything perfectly because it is all new to him.
He told People: "For a lot of new dads, you tend to dwell on the mistakes you don't want to make.
"I'm at that stage still where I'm focused primarily on being open and understanding and leaving a lot of room for error."

Iggy Pop loves to twerk around his house with his wife when a good song is played on the radio.
The 67-year-old rocker regularly throws some shapes with Nina Alu when they are chilling out together at home and admits the brunette beauty has mastered the dance style, which he thinks is partly down to her father being from Nigeria, Africa, where similar dances are traditional.
When asked what he thought of singer/songwriter Debbie Harry saying he invented twerking, he replied: "I was so proud.
"When something with a good beat comes on, I twerk around the house with my wife.
"Her father's Nigerian and she can twerk. And I try. I like to shake that thing."
While Iggy - who married Nina in 2008 - gets his thrills from twerking nowadays, the 'Really Wild Child' hitmaker used to get high on heroin, LSD, cocaine and alcohol, but claims he was rarely admitted to rehab because he was seen as a "hero" in the medical treatment facilities.
He added to Style magazine: "I was pretty alky for a couple of years. I went from grass to hashish to LSD to heroin. Then coke and heroin.
"Then down the steps from there to meth and Quaaludes. Then, finally, all the way down to outside the liquor store at 6am, waiting for them to open.
"Finally, little by little, I was able to wean myself off that with a combination of craft and willpower.
"I had two very good doctors in my life. One was a shrink, who admitted me at a key time into an actual mental ward, where I didn't really belong.
"Most people would have put me in rehab, but in rehab I was a hero.
"I went into one - I'd had a relapse in the early 1980s - and it was all, 'Hey Iggy, I've got some Valium, wanna have a Jacuzzi?' "
The Sailor Jerry 'Flash Collection by Iggy Pop' is available at Bolt London or www.sailorjerryclothing.com

Lorde's encounter with Pitbull was "not dissimilar to meeting the president".
The 18-year-old singer was so impressed by the 'Timber' hitmaker after she met him backstage at the American Music Awards last night (23.11.14), she took to Twitter to share the encounter with her 2.75 million followers and likened him to US leader Barack Obama.
She wrote on the site: "i met pitbull backstage, felt this wave of his charisma and loveliness wash over me, probably not dissimilar to meeting the president. (sic)"
Lorde - who performed her track 'Yellow Flicker Beat', which she penned for 'The Hunger Games: Mockingjay Part 1' soundtrack, at the ceremony in Los Angeles - also posted a cryptic tweet prior to her performance, which she described as the "saying farewell.. to this era".
She wrote: "performing yellow flicker beat tonight - it's gonna be a cool one; kind of saying farewell, for now, to this era. tune in from 5pm. (sic)"
The Grammy Award-winner was clearly looking forward to her evening, as she also posted: "AMAs-ing (sic)"
Unfortunately, the 'Royals' hitmaker - who was nominated for Artist of the Year, Favourite Female Artist, Favourite Album and Favourite Artist in the Alternative Rock category - didn't take any awards home at the ceremony in the Nokia Theatre, losing out on Artist of the Year to 5 Seconds of Summer, Favourite Female Artist to Katy Perry, Favourite Album to One Direction's 'Midnight Memories', and the Favourite Alternative Rock Artist to Imagine Dragons.

Jason Bateman would love to return to 'Arrested Development' to be back with his "beloved" Will Arnett.
The 45-year-old actor - who has been married to Amanda Anka since 2001 - is keen to reprise his role as Michael Bluth in the US sitcom so he can see the 'Teenage Mutant Ninja Turtles' actor on a daily basis once again.
He said: "Times were sweet when I could start my days with him and end my days with him on 'Arrested Development', you know.
"I'd get to work while the sun was still down and I'd get home after the sun's down. I'm with him all day, I didn't even see my ... you know ... the beard [his wife]. I'd leave before the beard gets up.
"So more 'Arrested Development' would be great, just so I could be back with my beloved."
Jason - who has daughters Francesca, eight, and two-year-old Maple - also joked he would love to see 44-year-old hunk's broad shoulders on set again.
Speaking on 'Conan', he added: "I think Will Arnett is one of the best human beings on the planet, I think he fills out a white v-neck like no one's business.
"He's got shoulders like a hanger."
'Arrested Development' originally ran on Fox from November 2003 to February 2006 and later returned in May 2013 on Netflix.
UK viewers can watch Jason Bateman's interview on 'Conan' at 11pm on Monday November 24th, on truTV (freeview channel 68) - the home of larger than life characters in real situations.