Olly Murs has apologised to Taylor Swift for poking fun at her songs after she said his comments were "sexist".

The former Xtra Factor presenter sent Taylor a hand-written apology after he found himself facing the wrath of the Shake It Off pop star, when he said she should "write something new" instead of writing songs about her ex, his friend One Direction singer Harry Styles.

"I reached out to Taylor around two days ago. I gave her a letter and said, 'I'm really sorry... It came out wrong. I'm sorry I didn't mean to make any offence'," he told Daily Mail Australia.

"She was landing in Sydney so I got a guy that I know to give it to her... I was told that it was personally delivered."

He added: "There's one thing - I'm not and I've never been sexist, I don't think that's right. It wasn't nice what I said, but it was a joke. I didn't expect it to blow up like it did."

He later told Australian radio station 2Day FM: " All I said was, 'Give him a break'. I have reached out to her, she knows I'm sorry, I didn't mean anything by it and it was all in jest."

Taylor, whose new song Into The Woods is rumoured to be about Harry, admitted the remarks felt like double standards.

"I have a really strict personal policy that I never name names. You're going to have people who are going to say, 'Oh you know she just writes songs about her ex boyfriends'," she told 2Day FM.

"But I think frankly that's a very sexist angle to take. No one says that about Ed Sheeran. No one says that about Bruno Mars. They are writing songs about their exes, their current girlfriends, their love life and no one raises a red flag there."