The One Direction star's vocals were leaked on Wednesday in a song called 'You', which he collaborated on with Wiz Khalifa and Juicy J.
Liam's vocals can be heard on the chorus of the hip-hop track, quite a move away from his boyband roots.
Liam, who sings the chorus on the song shared via TMZ, tweeted: "Hearing that I've got a single out lol thats a surprise to me that's a one take scratch demo I was writing with someone as an idea for them.
"Guess I need to guard my projects better ... They don't even let you finish these days. Just to clarify I do not have a single what u just heard is something I get up to on a weekend lol."
Liam and his bandmates Louis Tomlinson, Harry Styles and Niall Horan, announced their hiatus last year and are now taking a well-deserved break from group commitments.
But even their boss Simon Cowell admitted last month that he honestly doesn't know "if it's a hiatus or a break-up".
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