Nicole Kidman has hit troubled hubby Keith Urban with a new ultimatum: “No concert tours – unless I’m along for the ride!”

And the country music superstar has answered: “Baby, whatever you want. You’re my rock.”

That’s the latest development in the saga of the Oscar-winning actress and the Country Music Association Vocalist of the Year – as she stands by her man while he grapples with his substance abuse demons.

“She’s telling him that he can’t tour until she has a break in filming in April and can travel with him,” an insider told The ENQUIRER.

Keith’s long history of substance abuse dates back to 1998 when he checked himself into a treatment center for alcohol and drug addiction.

In mid-October, with Nicole at his side, 39-year-old Keith checked into the Betty Ford Center in Rancho Mirage, Calif. Since then he’s been released briefly to spend time with Nicole.

He’s living in a halfway house close to the facility, but he’s anxious to get on the road to promote his new CD, “Love, Pain & the Whole Crazy Thing.”

In the spring, Nicole’s scheduled to make a movie in Australia. After that, she’ll take a break so Keith can go back to work.

“Nicole understands now how fragile Keith’s sobriety is – and she wants to take every precaution to keep him off drugs and alcohol,” said the insider.

“At this point, there’s no way he’s going back on the road without her.”