Hollywood actress Olivia Wilde has blasted Justin Bieber for his bare-chested look, telling him to "put [his] f**king shirt on".

The Canadian superstar is in the UK at the moment as he takes his Believe world tour around Britain. Bieber was pictured returning to his London hotel in the early hours of the morning on Thursday topless, with his trousers sagging very low.

Wilde took to Twitter to slam the singer for his newfound sexy look.

Posting on the social networking site, she wrote: "Bieber, put your f**king shirt on. (unless you lost all your shirts in a fire in which case my condolences and please purchase a new shirt.) (sic)."

However, Bieber's fans were quick to jump to the hunk's defence, with one writing: "r u a lesbian or r u too old (sic)", which Wilde later retweeted.

It's not the first time Bieber has been embroiled in a Twitter feud.

The Canadian star and his manager Scooter Braun expressed their disappointment last year after the 'Believe' star missed out on nominations for the 2013 Grammys, which took place last month.

The Black Keys won a total of four gongs on the night and they managed to find time to slate Bieber, with drummer Patrick Carney joking: "He's rich, right? Grammys are for like music, not for money...and he's making a lot of money. He should be happy."

Bieber took to Twitter a couple of days later to write: "The black keys drummer should be slapped around haha (sic)."

19-year-old Justin was spotted in a pair of leopard print trousers as he returned to his London hotel in the early hours of Sunday following his Saturday night concert at the Capital FM Arena in Nottingham. Watch the lyric video for Bieber's 'Right Here':