Paul McCartney has opened up about collaborating with Kanye West on the track "FourFiveSeconds," which also featured Rihanna.

"I love Kanye," McCartney admitted during an appearance on BBC Radio 4 Mastertapes series.

"People say he's eccentric, which you'd have to agree with, but he's a monster, yeah. He's a crazy guy that comes up with great stuff. He inspires me."

"You just work with him and you leave him for a little while and let it marinate and hope he gets back to you," he added.

McCartney also discussed West's song "All Day," which he had a hand in writing.

"It's a great record, but when I got it, and I heard it, quite a few people said, 'You can't be connected with this.

There's like 40 'N-words,'" he recalled. "I said, 'Yeah, but it's Kanye and he's talking about an urban generation who uses that word in a completely different way,' so I was actually pleased with it."