Liv Tyler has posted a gushing tribute to her fiance David Gardner on Instagram.

Posting a picture of them together, with her engagement ring clearly visible, Liv wrote: "Crazy about my man!!!!! sweet sweet daddy, friend , fiancé thank you !!!!!! Grateful (sic)."

Liv - who also has 10-year-old son Milo from her marriage to musician Royston Langdon - is believed to have gotten engaged to the British sports agent in December 2014.

A source previously said: "They have been [engaged] since last Christmas but prefer to be private. She's been wearing the ring."

The 38-year-old actress recently admitted she was open to getting married again.

She said: "I had this philosophy that you should only get married once. But then, of course, that changes. I definitely believe we have lessons we learn through our relationships. You're meant to work through and mirror each other. It's the thing in someone that drives you the most crazy that is maybe a part of yourself somewhere."

Liv and David, who also has another son, Grey, seven, with ex-wife Davinia Taylor, currently divide their time between her home in New York City, his base in London and Austin, Texas, where she films her HBO series, but hope to be more settled in the future.

The brunette beauty said: "We're doing everything we can to be together, but right now because of work we're going back and forth."