Robert Pattinson was spotted in New York with the 28-year-old singer two weeks before he broke up Stewart.
"The couple (Robert Pattinson and Katy Perry) always liked each other.
There have been rumors about the "Swish Swish" singer and the Twilight actor for a few months, but there's been no proof that they're together.
They were the last to leave the Spot Lounge and, while there were no public display of affection, it was very clear they were extremely happy in each other's company," the source added.
But the rumors were denied at that time, saying that the two were just friends.