The Trainspotting author, 53, branded David Cameron’s efforts to prevent the break-up of the UK “pointless”.
He said: “Even unionists believed in independence now.
“Cameron has almost admitted as much.
“He’s saying that we should stay in the Union and he’ll give us tax-raising powers.
“Its about legacy. He doesn’t want to be seen as the British Prime Minister who oversaw the break up of the Union.”