A judge on Monday ordered Britney Spears to turn over custody of her two children to ex-husband Kevin Federline this week.

Los Angeles ? Britney Spears’ continuing downward spiral took a devastating turn Monday when she was ordered to relinquish custody of her children by a judge who had cited her drug-and-alcohol-fueled lifestyle.

Superior Court Judge Scott M. Gordon ruled that that ex-husband Kevin Federline will take Sean Preston, 2, and Jayden James, 1, beginning Wednesday “until further order of the court.”

The order stemmed from an unspecified oral motion made by Federline’s lawyers and was handled in a closed-door hearing. The judge’s order did not state the reason for the change in custody and he ordered all transcripts of the proceedings sealed.

Phone messages left for representatives of Spears and Federline were not immediately returned Monday.

Last month, Gordon said Spears engaged in “habitual, frequent and continuous use of controlled substances and alcohol” and ordered her to undergo random drug and alcohol testing twice a week as part of her ongoing custody dispute with Federline.

Spears also was previously ordered to meet weekly with a “parenting coach” who was to observe and report back to the court about her parenting skills. Both Spears and Federline must complete the court’s “Parenting Without Conflict” class.

Spears, 25, and Federline, 29, were married in October 2004. She filed for divorce last November and it became official in July. The two have joint custody of their sons, but Federline is seeking a greater share of custody.

Since Spears became single, her troubles have played out in the tabloids.

An MTV Video Music Awards performance last month meant to herald her comeback was universally panned, with Spears appearing spaced-out and lethargic – and, in some eyes, less than buff. The following week, Spears’ management firm dropped her and her divorce lawyer resigned.

She then was charged with misdemeanor counts of hit-and-run and driving without a valid license for allegedly crashing into a parked car in August.