Louis Tomlinson and Liam Payne have been working on new music with Good Charlotte.
The 'Midnight Memories' hitmakers joined Good Charlotte's Joel and Benji Madden at a studio in the United States on Saturday (08.03.14) to work on new tracks, which are expected to feature on One Direction's upcoming fourth album.
The collaborators took to social media sites to unveil the new partnership and speak about their excitement over the project.
Louis Tomlinson wrote: "Great working with the Good Charlotte boys today!"
Good Charlotte's Joel Madden then posted a picture of himself, Benji, Liam and Louis on his Tumblr page with the caption: "Noice! The London boyz putting in tha werk in the studio. (sic)"
Joel's twin brother Benji even teased that the new material could be a surprise to One Direction's fans - who are affectionately nicknamed "Directioners".
He wrote on Twitter: "Good day today w/ @Louis_Tomlinson and @Real_Liam_Payne lotta laughs #1D #Directioners their new album is crazy. homies #Noice (sic)"
Although Liam and Louis' bandmates - Harry Styles, Niall Horan and Zayn Malik - weren't involved in the collaboration, Harry has also been working on some new music as he teamed up with Irish rock band Kodaline last week.
The band posted a drawing on their Twitter page with the caption: "In the studio with @Harry_Styles in LA writing a tune, sounds massive. He's gone and done a drawing of us.. x (sic)."
One Direction began working on new material for their fourth studio album earlier this year and it's expected to be released later this year.

Helen George is still surprised by 'Call the Midwife's' success.
The actress - who plays nurse Trixie Franklin - admits she and the rest of the cast are amazed that the period drama has continuously managed to pull in high viewing figures after three years on air.
She said: "After the first episode of this series we were all saying how crazy it was to get such a ridiculously high figure three years in. There's always a sense of waiting for people to go, 'Actually, we're over this now', but luckily that hasn't happened yet."
Helen's character, Trixie, is currently being wooed on screen by newcomer Tom (Jack Ashton) and she has found the romantic scenes difficult.
She explained: "I find it really nerve-racking. Tom was my first screen kiss and it was mortifying. All the cast and crew were there wolf-whistling. And watching yourself kissing is the weirdest thing."
When she isn't playing a 1950s east London midwife, Helen loves watching American shows such as 'Girls' and 'Keeping Up with the Kardashians'.
She told Radio Times magazine: "I love 'Girls'. The writing's so clever. I think Lena Dunham is a genius, I can't believe she writes it, directs it and stars in it.
"I don't agree with everything [the Kardashians] stand for but I did shed a tear when Kris and Bruce [Jenner] announced they were getting a separation."

'Emmerdale's' Jane Cox broke down in tears filming Gemma Andrews' funeral.
The actress - who plays Lisa Dingle in the ITV soap - has revealed she was overcome with emotion filming the solemn scenes and couldn't stop tears from flowing as a children's choir serenaded the cast.
She told Inside Soap magazine: "Filming those funeral scenes was a very emotional day for all of us. The thing that really set me off was the lovely choir of kids singing 'Don't You Worry Child'. The purity of their voices really set me off and I just couldn't stop crying."
Jane's character Lisa is on edge this week as her daughter Belle (Eden Taylor-Draper), who is responsible for Gemma's death, is asked to speak at the teen's funeral.
Gemma (Tendai Rinomhota) died from head injuries following an argument with Belle in which she was pushed and hit her head against a rock.
Jane explained: "Belle thinks she killed Gemma so her guilt might make her do anything. And now Lisa is terrified about how Belle will cope.
"Lisa is the only one who knows what Belle is going through and she doesn't know what on earth she's going to say [at the funeral]. Luckily, she just reads out the lyrics of Gemma's favourite song. But after that she runs out of the church and Lisa fears she's heading for the police station."

Harry Styles has become a "virtual stranger" to his One Direction bandmates.
The 20-year-old heartthrob has reportedly been spending a lot of time in the United States with 'Keeping Up With The Kardashians' star Kendall Jenner and in turn has been neglecting his fellow 'Story of My Life' singers - who he will soon reunite with for rehearsals for their upcoming tour.
An insider claimed Harry had become a "virtual stranger" to the rest of the group, saying: "It's as if Harry isn't part of the group.
"It's going to come to a head now because for the first time in months they are going to be spending every day together as they rehearse for this summer's tour."
Harry's bandmates - Zayn Malik, Niall Horan, Louis Tomlinson and Liam Payne - are said to be worried that he isn't taking One Direction seriously and is instead more interested in pursuing his own career.
The insider told the Daily Star newspaper: "The boys want reassurances from Harry that he's in the group for the long haul. They won't let him just use them for his own career ambitions. They want to know what's really going on.
"It's like he has two separate lives now. One in America and his work with the band. Now he's going to come back in and act like they are all best mates again? It's unlikely!"

Union J's second album will be more acoustic than their debut.
The 'X Factor' formed boy band released their self-titled first album in 2013 after they came in fourth place on the talent show, but the youngest member of the group, George Shelley, claims they're going to have a lot more input in the second album.
Speaking exclusively to BANG Showbiz prior to their live set at M&M's World in London's Leicester Square on Thursday (06.02.14), he said: "We've been working on some new stuff and we're really enjoying it, it's very different. It's a lot more acoustic. It's more like folk and country music than before.
"We're happy we're getting to choose what we want to put out there as before we were kind of told what we were meant to be doing."
George and his bandmates - Josh Cuthbert, Jaymi Hensley and Jamie 'JJ' Hamblett - performed tracks including 'Loving You Is Easy' and 'Carry You' at the store to celebrate the launch of the new personalised M&M printer, and Jaymi said he hopes their new music will show how much they've grown once it's released.
He said: "We're a bit older now, you know? And it's been a year since 'X Factor' so we want to show that we've matured and I think that will come across in our new stuff."
The 24-year-old 'Carry You' hitmaker also revealed that he thinks their new single could be a contender for a Number One in Britain.
He added: "We've worked really hard on it and we're really happy with it so hopefully people will like it too."

Jessica Alba claims she doesn't mind who plays her character Sue Storm in the next 'Fantastic Four' movie.
The 32-year-old actress portrayed the invisible woman in the last two film adaptations of the comic book tales, but she will not be involved in the upcoming reboot as Kate Mara has been cast in the role.
When asked how she feels about Mara playing Sue, Alba replied: "I don't have any sort of real attachment to anything like that. I'm like, the more the better, I don't really have any idea. It's not like I created the comic book. I think Stan Lee [the co-creator of 'Fantastic Four'] should have a say in who plays Sue."
The blonde beauty also claimed she wasn't even aware of who had been cast as her replacement because she doesn't follow news.
She is quoted by the Belfast Telegraph newspaper as saying: "I don't read entertainment news so I'm not aware of it, but I love that comic book and it's such a great story about family and staying together.
"Morally, it's nice to have that series out in the world for young people to watch that. It's so positive. There's a lot of negativity out there and I really love the core of what that comic book is about. The more that's out there the better, I think it's great."
'Fantastic Four' is scheduled for release on June 19, 2015.

Nick Lachey is ready for a second child.
The 40-year-old singer and his wife Vanessa Minnillo, 33 - who got married in 2011 - are already parents to their 18-month-old son Camden, and are now thinking about increasing their brood.
He said: "We won't wait too much longer. I really want to have a little girl."
Nick also hopes when they do have a second child, the tiny tot will grow up to share the same temperament as well-behaved Camden.
He added to Us Weekly magazine: "Cam's got the best temperament ever, we can't imagine having a better kid than we do. He's an angel."
Meanwhile, Nick has a new job, hosting VH1's 'Big Morning Buzz Live!', and is eager to become healthier, so recently embarked on a juice cleanse to kick-start his weight loss plan.
He wrote on Twitter: "2014 is the year of getting healthy!! Time to get the diet right and dive into #crossfit Anybody with me? (sic)".
Nick has also completed a gruelling detox and has already noticed a difference in his body.
He wrote: "Well, the 5 day juice cleanse is officially over and somehow, i survived!! Thank you @OrchardFlats for cleaning up my 'act'. (sic)"

Winona Ryder's boyfriend is "very special".
The 42-year-old actress has been in a relationship with Scott Mackinlay Hahn for three years, and although she doesn't like speaking about their romance, she is proud of his work as CEO of ethical fashion brand Loomstate.
She said: "I try to just... It's not something I'm hiding but I learned early on not to talk about that. He's not in this industry.
"He's very special. What he does, which is incredible, is all about sustainability and helping companies go green. His work is pretty humbling."
Winona - who previously dated Johnny Depp - admits she used to worry about not finding someone who wanted to date her for who she is, rather than for her fame.
She recalled being hit on by a man in San Francisco when she was 35, only to realise she wasn't his usual type, but he was only interested in her because of her celebrity status.
She told Red magazine: "I remember getting this crushing feeling of, 'Am I ever going to meet someone who doesn't know anything about me, who doesn't think they know me because of what they've read on the internet?' "

Lena Dunham partied with Taylor Swift at the 'Saturday Night Live' after-party yesterday (08.03.14).
The 'Girls' star, who fronted the NBC show last night, celebrated her hosting debut with the 'Everything Has Changed' singer at the bash, held at Asselina restaurant in Union Square, New York City.
'Saturday Night Live' cast members - Aidy Bryant, Bobby Moynihan and Vanessa Bayer - were also in attendance, as was 'Mean Girls' star Daniel Franzese, who took the opportunity to grab a photograph with Taylor, 24, and other party-goers, according to E! News.
Lena, 27, took to Twitter after the gathering to gush about her experience on the show.
She wrote: "Cannot overstate how joyful this experience has been. I have always loved you Saturday Night Live, but now I am IN love with you (sic)".
Meanwhile, the brunette beauty opened the programme with a hilarious spoof video based on the biblical film 'Noah', which saw her running through the Garden of Eden without any clothes on.
Speaking in her opening monologue, she said: "There is an old saying: If you're nervous about giving a speech, just imagine the audience naked. Or at least imagine that they haven't seen you naked."

Kourtney Kardashian wants her wedding to be just as "spectacular" as her sister Kim Kardashian's big day.
The reality TV star is reportedly planning to tie the knot with her partner Scott Disick, but she's worried her ceremony will be overshadowed by Kim and Kanye West's nuptials this summer.
A source told RadarOnline: "Kourtney has already seen Kim have an over-the-top wedding with Kris Humphries and now she's watching her sister turn her Kanye West date into another big affair and she's getting mad that her own wedding is going to be overshadowed.
"She wants her wedding to be just as spectacular as Kim's."
Kourtney and Scott - who have Mason, four, and one-year-old daughter Penelope together - are reportedly keen to wed in Mexico, while Kim, 33, and Kanye, 36, who have eight-month-old daughter North together, are getting hitched in Paris, France.
The source added: "For a really long time Kourtney has felt like she is living in Kim's shadow but she doesn't want her wedding to be second to Kim's third trip down the aisle.
"Everyone knows that Kim is the most popular sister and Kourtney really wanted her wedding to be special, so she's not planning to let Kim steal her spotlight now."
Meanwhile, the couple - who have been together for over seven years - are planning an intimate wedding and will splash out $100,000 on round trip private jet flights for their loved ones, as well as $30,000 a night on accommodation.

Kate Upton has reportedly threatened to sue a website after it allegedly posted fake pictures of her naked.
The 21-year-old model is taking legal action against a joke company, Celeb Jihad, after it allegedly edited topless images of the blonde beauty from her Sports Illustrated magazine shoot with the headline, "Kate Upton Naked Outtake From SI Swimsuit 2014".
Kate's legal team immediately sent the website a letter threatening to sue if it didn't remove the fake snapshots straight away.
According to TMZ.com, Kate's lawyers were not only concerned about the photos containing the star's breasts, but they also claimed in the letter that the pictures had been airbrushed.
Celeb Jihad has since removed the images, which it reportedly branded "boring" and "horrible", from its website.
This isn't the first time the company has come under fire for editing photographs after it allegedly published a snap of a topless, blonde, woman, which it claimed was Taylor Swift in 2011.
The 24-year-old singer's legal team reportedly threatened to sue for wrong identification and for trademark infringement.
However, the picture was taken down immediately.

Ray Quinn has been crowned the champion of 'Dancing on Ice'.
The 25-year-old singer and his professional partner Maria Filippov won the all-star last-ever series tonight (09.03.14) after he beat runner-up 'Coronation Street' star Hayley Tamaddon to the title.
Speaking after his win, Ray - who also won the show back in 2009 - said: "It feels so good [to win] ... but this moment for me is for Maria. I'm absolutely buzzing. I'm over the moon, honest to God."
Before he joked: "Drinks are on me!".
Both Hayley and Ray secured impressive marks from the judges throughout the show, with the former 'X Factor' star receiving a top score of 80, while the actress followed closely behind with 79.5.
The pair took to the ice to perform three routines - including the famous Bolero - in a bid to show off their daring moves and wow over both the audience and the judges.
Meanwhile, earlier in the night, Olympic gymnast Beth Tweddle, who won the show last year, and her partner Łukasz Różyck came in third place after they failed to secure enough votes.
Tonight's episode also saw professional skaters Jayne Torvill and Christopher Dean give their last-ever televised performance of their iconic 1984 Olympic routine.
While the judges - Robin Cousins, Jason Gardiner, Ashley Roberts and Karen Barber - also slipped on a pair of skates for a one-off performance at the beginning of the programme.
Hosts Phillip Schofield and Christine Bleakley also had a go at gliding across the ice, before former presenter Holly Willoughby - who left the show in 2011 - came out to give Jayne and Chris a stunning collage of photographs to mark the end of the series.