He swore off marriage after two divorces, but 24 star Kiefer Sutherland is ready to take the plunge again!

The ENQUIRER has learned the rugged Emmy winner is ring shopping and ready to propose to his girlfriend of two years, Allure magazine’s style director Siobhan Bonnouvrier.

Pals say Kiefer, 43, is so in love with the sexy 39-year-old New Yorker that he had this season’s production of the hit FOX show moved to the Big Apple.

"Kiefer believes in his heart that Siobhan is his soul mate," a friend told The ENQUIRER.

"Even though he’s been married twice before, he says that he’s never felt so strongly about a woman. He even persuaded producers to move the set of 24 from the West Coast to New York because he can’t stand to be away from her."

After divorcing his first wife, actress Camelia Kath, in 1990, Kiefer married model Kelly Winn in 1996. They separated in 1999, but the divorce wasn’t final until May 2008.

He and Siobhan, who’s also divorced, had been friends for two years before they started dating in April 2008, sources say.

Soon after they met, the actor plunked down $8.25 million for a five-story townhome in Manhattan’s West Village because he said he "felt in his bones" that they’d live in it together one day, the friend said.

As The ENQUIRER reported in April 2008, after serving 48 days in a Los Angeles jail for his fourth DUI arrest, Kiefer made a commitment to get his life straightened out to have a future with Siobhan.

"Right now, he’s obsessed with finding the perfect engagement ring," the source divulged.

"Kiefer is taking his time, but he wants to propose around Valentine’s Day."