Michael Buble has hailed Sir Paul McCartney "a wonderful leader".

The 'Haven't Met You Yet' hitmaker got to work with the Beatles legend on a cover of McCartney's 2012 solo song 'My Valentine' - a love letter to his wife Nancy Shevell - which features on Michael's new album, 'Higher', out now.

And the Canadian star has praised the 'Let it Be' hitmaker for lifting the spirits of everyone in the studio.

Speaking in an interview with The Sun newspaper, Michael said: “He lifted everybody, he’s a wonderful leader.

“I’d asked his manager if he wanted to be involved and started working on an arrangement for it.

"The concept I had was, 'It Was A Very Good Year' by Frank Sinatra.”

Before heading to the studio together, Michael sent a demo of the track to Macca, 79, and earned his praises.

Michael recalled: “He said, ‘This is wonderful’. He was so sweet. He was really lovely because this song means so much to him as he wrote it for his wife Nancy.”

The 'Home' singer also got to duet with his hero Willie Nelson, 88, on a cover of his hit 'Crazy', which was popularised by country singer Patsy Cline in 1961.

He gushed: “Willie Nelson is my hero, one of my top ten favourite singers of all time.

“He’s one of the greatest storytellers. His record 'Stardust' was a big part of my life."

The 46-year-old singer - whose last studio album was 2018's 'Love' - hopes he's done the originals "justice" and believes, as an "elder statesmen" of the music industry, he's earned the right to work with icons.

Michael added: “You know how they say timing is everything and I think maybe it was my time. Maybe I earned the right to work with these people.

"Not because of talent but because I’ve made 11 records now.

“I don’t want to say I’m an elder statesman, but you know, I’ve been here a while now.

“I think I put enough love and enough reverence in these songs. I hope I earned the right to be able to say that I was responsible in interpreting these songs and doing them justice.”