The 75-year-old music icon has backed a newly proposed law to protest music venues from closure.
Labour MP John Spellar, who served as a minister under Tony Blair and Gordon Brown, has introduced a bill in the House of Commons on the matter.
According to Sky, alongside Sir Paul other musicians to back the proposed legislature include Pink Floyd drummer Nick Mason, Craig David, Ray Davies, Billy Bragg, Chrissie Hynde, Sandie Shaw and Feargal Sharkey.
In a statement, Sir Paul said: “Without the grassroots clubs, pubs and music venues my career could have been very different.”
The Beatles star added: “If we don’t support music at this level, then the future of music in general is in danger.”
If the law is passed, developers will be forced to consider the impact of new schemes on businesses, like music venues, before taking planned action.
McCartney revealed: “There’s a million ways to write, but the way I always used to write was with John and it would be across from each other, either in a hotel bedroom on the twin beds, with an acoustic guitar and we’re just looking at each other.”
He added: “He’d make up something, I’d make up something and we’d just spin off each other.”
“The nice thing for me is seeing John there, him being right-handed, me being left-handed, it felt to me like I was looking in a mirror.
“Obviously, it was very successful. So that was a way I had learned to write and it was the way I liked to write and Elvis [Costello, his new collaborator] was very happy to work like that.
“So it was like a repeat of that process, and so he was John, basically, and I was Paul.”