Harry Potter star Daniel Radcliffe has again addressed rumours that he is gay.

The 20-year-old star is becoming known as a gay rights activist for his support of the Trevor Project, a helpline for suicidal LGBT people.

He gave the charity a large donation last year and has volunteered to appear in an advert against homophobia this spring.

The star has also appeared in the cover of gay magazine Attitude.

Despite having had girlfriends, he is the subject of persistent internet rumours that he is gay.

He told MTV yesterday: “If people want to say that, they can. I’m not. I’m straight.”

He added: “My favourite thing I saw was a guy on the internet who said, ‘Of course he’s gay – he’s got a gay face,’ which I thought was kind of an odd thing to say anyway.

“A gay face? That’s a very worrying thing, like they have sat at home with pictures of me next to other famous gay folks.”

Speaking about the advert earlier this week, the star said he had grown up around gay people but was now in the “very fortunate position” of being able to do something about homophobia.