Kiefer Sutherland is beginning a jail term after being formally sentenced yesterday to 48 days for drunken driving.

The Jack Bauer actor had planned to do his time in two separate stints so as not to interfere with production on hit show 24.

However, he will now his serve the 48 days consecutively after the screenwriters' strike halted filming on the Fox show.

Kifer was arrested in September while still on probation for a 2004 drunken driving offense.

In October, he pleaded no contest to a single count of driving with a blood alcohol level above the legal limit.

His celebu-lawyer, Blair Berk, told Reuters that the actor would turn himself in on Wednesday evening to begin serving his sentence immediately.

Kiefer was placed on five years' probation, fined $510, and ordered to enroll in an 18-month alcohol education-treatment program and to attend six months of weekly alcohol counseling sessions.