HOLLYWOOD: Vanessa Hudgens is suing a US website for posting a nude self-portrait of the High School Musical star.

The 21-year-old actress is taking the owners of www.moejackson.com to court, claiming that the website posted and refused to remove nude 'self-portrait photographs' taken on a mobile phone in a private home.

The lawsuit says that Hudgens didn't know anything about the pictures or how the internet site managed to get them.

'The photos were obtained by unknown methods and posted on the internet by an unknown person without Hudgens' knowledge or consent,' the lawsuit explains.

However, the nude pictures were registered with the US Copyright Office.

Hudgens' lawyers claim that posting the pictures is a copyright violation, but the company that owns the site, Butter Media are prepared to take it to the courts.

Hudgens has filed a federal suit, asking for an injunction and ordered the site to take the pictures down. She is also claiming damages.