MJAA / ZDS / WENN 1 / 13
MJAA / ZDS / WENN 1 / 13

Friendly exes or rekindled flames? Katy Perry sparked reunion rumors when she was spotted out in London on Wednesday night with her recent ex, Florence + the Machine guitarist Robert Ackroyd.

The pair, whose monthlong fling kicked off in April with PDA galore at the Coachella Music Festival, started their evening at local hot spot The Dove before heading to a warehouse party, where they hung out into the wee hours.

Katy, 27, who was rocking a green dress, a black leather jacket and purple tresses, tried to keep her distance from Ackroyd in front of the paparazzi (see pic below), which is quite a change from their previous public handsiness.

The soon-to-be-ex-Mrs. Russell Brand supposedly called time on the romance in mid-May because of career commitments and trust issues.

"Rob is a good guy, but she just wants to focus on her work," a source told E! News. "She's still dealing with getting over her marriage, and it's going to take her a while to truly be able to trust anyone again."

Us Weekly echoed the amicable nature of their split.

"It's not a nasty thing, and they are still talking, but Katy told him to do his thing and they'll talk soon," a source explained, with another adding, "No hard feelings. She's really busy and so is he."

Whatever the state of her relationship with the strapping Ackroyd, she still has her friends -- and her sense of humor. During a recent radio station interview, Katy was asked whether she was planning a musical collaboration with BFF Rihanna.

"No," she said. "But we're gonna have sex."


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