Viewers are convinced Katy Perry just threw shade at 'enemy' Taylor Swift on national TV.

Hello and welcome to (what feels like) round 647 of Katy Perry versus Taylor Swift.

It’s been so long since gossip magazines the world claimed that the former friends had become sworn enemies, we can’t even remember how this whole thing started.

Perhaps it’s something about Katy stealing Taylor’s back-up dancers. Or was it due to the fact both pop singers had romantic connections to John Mayer?

Maybe there just wasn’t all that much happening in celeb land one week and creating a feud between two of the world’s most successful female singers was the quickest way to make a buck.

Anyway, here we are, in March of 2018, speaking about it YET AGAIN, because apparently, Katy Perry has "thrown shade" at her 28-year-old rival on one of America's most watched television programs.

As a judge on a re-booted version of talent show American Idol, Katy Perry was forced to sit and listen as an aspiring contestant confessed that the country-turned-pop singer was his biggest inspiration.

Watch Katy Perry apparently throw shade at pop 'rival' Taylor Swift on American Idol:

"I'm sorry for this Katy..." the contestant began. "Taylor Swift... I love Taylor Swift."

Katy was quick to respond.

"Oh you don't have to be sorry at all!" she said, before adding, "I love her as a songwriter as well."

AS.

A.

SONGWRITER.

It's a curious comment for Katy to have made, considering the two have (supposedly) been taking aim at one another through their song lyrics for years.

Remember Taylor's Bad Blood? In which she claims there used to be "mad love" and now "we got problems / and I don't think we can solve them"?

She was speaking about Katy Perry.

And the 33-year-old responded in her 2017 track Swish, Swish, telling Taylor, "funny my name keeps comin' out your mouth / 'Cause I stay winning".

"Your game is tired / You should retire / You're 'bout as cute as / An old coupon expired," she added.

It's also odd, since she told Arianna Huffington last June she was "absolutely, 100 per cent ready" to end her feud with the singer.

"I forgive her, and I'm sorry for anything I ever did, and I hope the same from her, and I think it's time," Katy said.

"There are bigger fish to fry, and there are bigger problems in the world."

Whatever the reasoning behind Katy's latest comment, there's one thing for sure: Katy's American Idol stunts are definitely keeping the show in the news.

Last week, she came under fire for 'surprising' a 19-year-old contestant with his first kiss.

LISTEN: Taylor Swift has a new image, and we're not sure it's a positive one. The Mamamia Out Loud team discuss.

Want to win some skin care goodies? Like to have your opinion heard?
Take our short survey now for your chance to a win a skin care pack.