Katy Perry reportedly "hooked up" with Mumford and Son's Winston Marshall in Berlin on Saturday (14.03.15).

Katy Perry

Katy Perry

The 30-year-old singer has sparked speculation she's split from John Mayer once again after she was spotted getting close to the British rocker, 26, following her concert at the O2 Arena.

The folk group met up with the 'Roar' hitmaker following their intimate show at the Magnet Club in the German capital and reportedly danced the night away at the trendy nightclub Schwuz, according to the New York Daily News' Confidential column.

This wouldn't be the first time a member of the popular band has found love with an A-list celebrity as the lead singer Marcus Mumford is married to Hollywood actress Carey Mulligan, 29.

Katy and John, 36 - who have had an on-off relationship since 2012 - rekindled their relationship earlier this year after splitting last February and were determined to make their romance work this time around because they'd both "changed" as people.

A source said last month: "It's different this time around. Both of them have changed, and after nearly a year apart they've realised what they want."

Meanwhile, Katy's ex-husband British comedian Russell Brand, whom she was married to from 2010 until 2012, is planning to reveal all about their short-lived marriage in his new documentary 'BRAND: A Second Coming' later this week at the SXSW festival.