The One Direction singer, 22, is reportedly 'incredibly sad' that their two-year relationship has come to an end.
Speculation about their romance intensified on Saturday (24 October) when Liam posted a cryptic tweet to his 21.1million followers.
He said: "I love how music is always there for you when you need it most x."
I love how music is always there for you when you need it most x— Liam (@Real_Liam_Payne) October 24, 2015
Liam pulled out of a Belfast gig at the last-minute this week, with a statement revealing that he was too sick to perform.
Now, a source tells the Sunday Mirror: "Liam and Sophia have split up. Liam is incredibly sad, but is going to keep busy.
"He really hopes that everybody will respect both his and Sophia's privacy and stop speculating."
Neither Liam or fashion business student Sophia have publicly commented on the alleged split so far.
They have known each other since meeting at school in Wolverhampton, before Liam found fame on The X Factor.
In August, One Direction announced they are planning to take an extended break from March, after completing their On The Road Tour and releasing their fifth studio album, Made In The A.M.
It's turning out to be an eventful year for the band, now a four-piece after Zayn Malik left in March.
Louis Tomlinson split from his long-term girlfriend Eleanor Calder earlier this year, and is now expecting a child with Briana Jungwirth following a brief relationship.
Zayn called off his engagement to Perrie Edwards, while singletons Harry Styles and Niall Horan have been linked to too many women to mention!
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