However, now the former X Factor stars might be about to reunite in full for the first time as they're rumoured to be appearing as guests for the final ever edition of James Corden's Late Late Show. The popular host revealed that he was bringing his long-time hosting of the show to an end last year and his final episode is set to air on 27 April.
The guest list for the final episode is understandably being kept under tight wraps, but it has been confirmed that the Kardashians will be playing a role.
The rumour mill is confident that One Direction will be part of that line-up, given that James has stated how much of a fan of the boyband he is.
Louis Tomlinson also had to cancel the Asian leg of his current tour, including dates that will fall on James' last hosting of the show, due to "unforseen circumstances".
The band, sans Zayn, have previously appeared on the show and James is incredibly close with its members with the host having met the band when they were just becoming famous.
He previously joked about "babysitting" its members when Louis' late mum reached out to him to keep an eye on her son when he was in London.
"Various members of that band would come around to our house in North London and we’d eat pizza and play PlayStation and my wife [Julia] would feel like she was babysitting," he told People when asked about his relationship with Harry. "And then from then on, our friendship has grown, and I love him [Harry] very, very much. I’m very proud of him and protective of him, always."
James even appeared in the music video for Harry's hit song Daylight, in which the pair crashed the apartment of some fans.
Zayn left the band in 2015, saying in a statement: "I'd like to apologise to the fans if I've let anyone down, but I have to do what feels right in my heart. I am leaving because I want to be a normal 22-year-old who is able to relax and have some private time out of the spotlight. I know I have four friends for life in Louis, Liam, Harry and Niall. I know they will continue to be the best band in the world."
The group later split in 2016 with the remaining members focusing on their own projects.
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