Lily Allen. (AP File)

Pop star Lily Allen has defended her decision to pose topless for a new magazine photo shoot after she was criticized for the saucy snaps online.

The Smile hitmaker can be seen baring her breasts for the latest edition of design publication i-D in a series of revealing pictures.

The daring images attracted some snide comments from outspoken celebrity blogger Perez Hilton, who was engaged in a bitter war of words with Allen earlier this year.

He wrote on his website, "More known for her outrageous behaviour than her music, Lily Allen continues with her 'antics'. The hard-pAArtying (sic) Brit goes topless in the new issue of i-D magazine. Why? Well, why not??? We've already seen 'em before - a lot!"

But Allen has hit back, insisting she's not ashamed of her naked form.

And she couldn't resist poking fun at Hilton's figure as she replied to his comments.

She writes on her Twitter.com page, "Just saw Perez's views on my topless i-D pics. It may come as a surprise but I'm completely comfortable with getting them out. T**s are t**s.

"I wish mine were as big as Perez Hilton's though."