David Hasselhoff has sparked rumours he is engaged.

The TV star has posted a series of cryptic messages on his Twitter page including a picture of himself and his girlfriend Hayley Roberts on top of Sydney Harbour Bridge in Australia.

The photograph shows David on a bended knee, while Hayley is smiling toward to camera.

It boasts the accompanying caption: "Tried it again on top of the Sydney harbour bridge (sic)!"

Immediately afterwards, the 59-year-old posted another picture of the pair in a passionate embrace.

He captioned the romantic image with the words: "What do you think she said (sic)?!"

Hayley didn't confirm or deny the engagement news on Twitter. However the Welsh beauty posted a suggestive message on her social networking page.

":-)))))) xxxxxxxxxxxx (sic)," she wrote.

David and Hayley Roberts, 32, have been dating for nearly a year.

Hayley has already turned down several marriage proposals from 59-year-old David.

A representative for the actor has yet to confirm the news.