Miley Cyrus has confirmed her engagement to her partner of four years, musician Maxx Morando.

The three-time Grammy winner was seen wearing a gold and diamond ring on her engagement finger at the premiere of Avatar: Fire and Ash in Los Angeles on Monday.

In an interview with US TV show Good Morning America on Wednesday, the 33-year-old said Morando had got down on one knee for the proposal during a recent trip to Asia.

"I am not easy to surprise because I love to control every situation and I had completely surrendered and I'm telling you, I was so, so, so surprised," she said.

Cyrus, whose hits include Flowers and Party in the U.S.A, previously married Australian actor Liam Hemsworth in 2018.