Willie Nelson popped into “The Tonight Show” on Friday for a virtual visit with Jimmy Fallon.

Among the topics of conversation were “I’d Want It to Be You”, his recently released duet with Barbra Streisand, originally recorded for her 2014 Partners album but finally unveiled on Release Me 2, Streisand’s new compilation of unreleased tracks.

“She’s always been one of my favourite people, great singer. We had a lot of fun hanging out with her back when they were doing ‘A Star Is Born’ with Kris Kristofferson,” Nelson said.

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“We became good friends, so I was glad to be able to sing with her, she’s a great singer, and one of my desires was to do a duet with Barbra,” added Nelson.

Nelson also discussed his new book Letters to America, which he described as “a collection of fond memories, personal letters, good songs and bad jokes.”

Asked what inspired the book, Nelson joked, “I don’t know; someone said something about money… I thought it was a good idea, and Turk Pipkin and I — the writer who helped me with the book, a good friend of mine — we’d done a lot of things together in the past, so I had a lot of fun doing it.”

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Meanwhile, Nelson will be heading out on the road soon with his Outlaw Music Festival, which will mark the first time he’s performed in front of an audience since the COVID-19 pandemic shut down live performance in March 2020.

“I’m glad to get back out, it’s been over a year now, and I’m not sure I can remember ‘Whiskey River,’” he added.