Pink Floyd rocker Roger Waters uses an imaginary Sir Paul McCartney to diffuse tension when he is working in the studio.

The COMFORTABLY NUMB hitmaker, who has just premiered his opera CA IRA (THERE IS HOPE) in Italy, pretends the former beatle has all the ideas in the studio so he can dismiss his producer's less-than-helpful suggestions politely.

The 62-year-old says, "We've developed what I think is a very good way of dealing with the politics of the control room.

"We pretend Paul is thinking of all the ideas - so when it's a bad idea, I'll wag my finger and say, 'That was Paul, wasn't it?'

"We have a laugh about it and it defuses the situation."