US Senator John McCain has been remembered as a “true friend of Australia” by new Prime Minister Scott Morrison.

McCain died at the age of 81 on Sunday surrounded by family at his Arizona home, after battling brain cancer.

The prime minister paid tribute to the man he says “was a true friend of Australia, who was committed to strengthening the alliance between our two nations”.

“He was a man of great courage and conviction. Our thoughts and prayers go out to his wife, Cindy, and all the McCain family during this time,” Mr Morrison tweeted on Sunday.

Australia’s Ambassador to the United States Joe Hockey also paid his respects to the war hero.

“How terribly sad to hear that Senator John McCain has passed away,” he wrote on twitter.

“People who love justice, democracy, freedom and courage will mourn this loss of an American legend.”