Harry Potter star Daniel Radcliffe has denied newspaper reports he smoked cannabis at a party in London.

On Friday, the Daily Mirror published a photograph which allegedly showed the 20-year-old actor taking the drug.

According to the Daily Mirror, Radcliffe, who plays the boy wizard, repeatedly took drags on a spliff during the private gathering.

However, a spokeswoman for Radcliffe has “categorically” denied the reports.

"Daniel does smoke the occasional roll-up cigarette, but he was not doing anything more than this,” she told the BBC.

"We are considering our position and will be taking all necessary action in relation to such allegations.”

Radcliffe shot to fame when he was cast as Harry Potter at the age of 12.

After making his name on the silver screen, the actor moved to the stage three years ago in the West End show Equus.

The production, which later moved the Broadway, was praised by critics and fans.

The most recent Harry Potter film, Harry Potter and the Half-Blood Prince, was released last summer.

On the set of Harry Potter