The former Hannah Montana star, who met Hemsworth on the set of flick The Last Song in 2009, has been dating Liam for three years - with her rep now revealing the couple are engaged.
In a statement, the Party In The USA hitmaker told People: "I'm so happy to be engaged and look forward to a life of happiness with Liam."
The Hunger Games hunk is said to have asked the 19-year old to be his wife on 31st May, presenting Miley with a 3.5-carat diamond from jeweller Neil Lane.
Cyrus previously fuelled rumours that she was engaged to Liam back in March, after she tweeted snaps of herself wearing a huge diamond sparkler on her left hand.
Earlier this month, the Can't Be Tamed star hit the headlines after describing sex as "a beautiful thing."
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