United Kingdom, April 14 -- Kevin Federline is "happy" Britney Spears has entered rehab after her recent DUI arrest.

The 48-year-old pop star's representatives confirmed over the weekend that she has voluntarily entered a treatment facility five weeks after being arrested on suspicion of driving under the influence of drugs and alcohol early last month.

Her ex-husband's attorney Mark Vincent Kaplan told TMZ in a statement: "Kevin is aware of the reports that she has checked into rehab and that if she needs help, he is happy that she is getting help and that the decision appears to be one that she made and not one imposed upon her by others if it was.

"The key is that whatever the recommended treatment plan is that she follows it and co...