Miley Cyrus has defended herself after she was criticised for frolicking in a pool with a male friend less than two weeks after getting engaged to Liam Hemsworth.

The singer/actress, who is set to marry The Hunger Games star after he popped the question on 31 May, raised eyebrows after she was photographed enjoying a dip with her guy pal Cheyne Thomas on Tuesday.

The pair was spotted sharing a floating mattress in the pool and enjoying drinks on sunloungers at the star's hotel in Miami, Florida, prompting speculation Cyrus' romance with Aussie hunk Hemsworth is in trouble.

However, Cyrus has now taken to Twitter.com to set the record straight, insisting Thomas is just a friend.

In a series of posts, she writes, "I love my fiance & he loves me. All the rest is bull s**t. We get to live a life of happiness, no one can take that away from us!

"So now because I am engaged I can't have a friend of the opposite sex? Can't have a friend help me out while I'm working all day? Dumb." (PAW/WNWCDAM/ZN)