NEW YORK - Kiefer Sutherland's legal troubles for allegedly head-butting a fashion designer in a New York City nightclub are over.

The Manhattan district attorney's spokeswoman said Tuesday that misdemeanour assault charges against the actor are being dropped because the alleged victim wouldn't co-operate with prosecutors.

The star of the Fox TV show "24" was charged in May after designer Jack McCollough said Sutherland head-butted him and broke his nose in a Manhattan nightclub.

Sutherland and McCollough issued a joint statement a few weeks later saying they had resolved their differences. Sutherland apologized to McCollough in the statement.

Sutherland's attorneys declined to comment Tuesday.