Former Northern Ireland secretary Mo Mowlam has warned of the "destructive" relationship between prime minister Tony Blair and chancellor Gordon Brown.

In a documentary for Channel Four, "Mo Mowlam: Inside Labour", she also accuses former colleagues of a "vicious, violent, appalling" smear campaign against her.

However, Downing Street has denied the claim. "No journalists have ever been able to say that Number 10 briefed against Mo, because it is simply not true," a spokesman said.