Sutherland 'really regrets' alleged headbutt

Kiefer Sutherland has admitted that he "really regrets" his altercation with fashion designer Jack McCollough.

Earlier this month, the 24 star was charged with misdemeanour assault after allegedly headbutting McCollough in a dispute over actress Brooke Shields.

When asked about the incident on Late Night by host Jimmy Fallon, Sutherland said: "We can joke about it but it's something I really regret having happened. And until it's kind of resolved, I really can't talk about it."

Later on in the interview, the actor told Fallon that bloopers from 24 have been saved for a future release.

"We've actually saved bloopers for about seven seasons. I think we're going to save them for the final year," he said. "The show is so serious - when something does go wrong it's unbelievably funny."