The singer has a haemorrhaging nodule on his vocal cord and is set to undergo surgery on Thursday in a bid to save his voice.
The band have been thrown into disarray, as the op means that he won't be able to talk for a month, let alone sing, and the lads are meant to be in the studio recording their new album and planning their world tour for later this year.
“It’s not good at all. Nathan has battled with throat issues for a while but this is far more serious," they said.
“After the once-over by the specialist, he was instructed to have almost immediate surgery. Naturally Nathan is really worried as if it doesn’t work, his career is over."
They added: “It will be tricky to continue [the group] without him as vocals will have to be changed. All their worldwide commitments are having to be put on hold.”
An official statement from the group's spokesperson confirmed the news, but insisted the the four remaining members will continue with their commitments during Nathan's absence.
"We can confirm that The Wanted's Nathan Sykes will under go specialist throat surgery on Thursday 18th April in Los Angeles and as such will be taking unforeseen hiatus from The Wanted," it read.
"The priority for Nathan, his label and management is that he is given time to recover and receive the best treatment possible.
"The remaining four members of The Wanted will continue fulfilling the bands promotional commitments across the world."
The news comes just as it is revealed that he has split from girlfriend Dionne Bromfield.
After much speculation, the couple finally confirmed their romance earlier this year when they were pictured smooching on holiday, but Dionne has revealed it's now over.
"No we're not dating, not any more," she told Entertainmentwise. "Yeah, it is [difficult] but you know, we're really good friends so there are no hard feelings at all."