It seems that Katy Perry knows how to hold a grudge - following years of an alleged feud with fellow singer Taylor Swift it has now been suggested the I Kissed a Girl hitmaker went on a date with The Weeknd in revenge after his own ex-girlfriend, Selena Gomez, stepped out with her ex, Orlando Bloom.

Katy PerryAre Katy Perry and The Weeknd really dating?

The Sun reported that sources closest to the star revealed it was an act of 'revenge' after The Weeknd's ex Selena Gomez embarrassed Katy, 33, by joining her own ex Orlando Bloom for dinner one night in May while they were still together.

The source claimed: "Katy has a long memory and she never forgets.

"She didn't like that everyone thought Orlando had cheated on her with Selena in Vegas that time - even though Orlando and Selena said they were just friends, it was very embarrassing for her.

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"Katy is not doing anything wrong right now - Selena has moved on from [The Weeknd] with Justin [Bieber] but I think she'll love the idea that Selena will be shocked when she sees Katy and her ex out together.

"If she does get upset, it'll be payback for how Katy felt after those Vegas pictures.

"As Taylor Swift knows, Katy doesn't forget people who've made her look bad, and she thinks revenge is a dish best served cold."

The Weeknd and Katy went to Madeo Restaurant in West Hollywood on Monday night.

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The Canadian singer - real name Abel Makkonen Tesfaye - and Katy arrived separately to the eatery, before joining each other at a table inside for three hours.

According to one source, the duo were sat inside the Italian restaurant until midnight before heading home separately in different vehicles.

Katy has previously been married to British funnyman Russell Brand, also dating Orlando Bloom and singer John Mayer.