Says BBC News:
Downing Street has denied rumours of a feud between cats belonging to the chancellor and prime minister after they were pictured fighting. George Osborne's Freya was photographed slugging David Cameron's Larry with a nasty-looking left claw, the evidence being posted on Twitter.And here is the picture - thanks to @PoliticalPics - though, to be honest, it looks a little too good to be true.
Still, never believe anything until it has been officially denied...
Later. The Daily Telegraph assures us the photo is genuine.