Britney and Paris Hilton

Britney Spears has splashed out more than $US3000 on underwear - despite constantly being pictured without it.

The Toxic singer - who has been partying hard since she filed for divorce from Kevin Federline earlier this month - visited trendy Hollywood boutique Le Bra Lingerie to buy several thongs and bras.

A source told gossip website TMZ.com: "Britney came in with a female friend. She tried on everything she bought. She's a 36C. She said to her friend, 'I could live here.'"

Among the mother-of-two's purchases were a camisole and thong for $US1315, a bustier and thong for $US510, a black corset and matching red thong for $US300 and a yellow bra and thong for $US333.

Britney's recent partying with new pal Paris Hilton has attracted a lot of criticism, partly because of her habit for accidentally exposing herself.

Her fans have posted messages on her official MySpace page urging her to clean up her act. One post read: "I hope you read this so you understand how your fans may see the situation. Now your children need you so do the right thing Brit and be a mother and forget the partying."

Celebrity image consultant Amanda Sanders said: "She's a beautiful girl and now she's single she's having fun, I think she's just trying to express herself.

"Unfortunately, it's the wrong message that's coming across. And the shame is she was really such a role model.

"She's worth millions and probably has fabulous things spilling out of her closet. Now she's got awful extensions and her hair just looks cheap."

Entertainment Weekly magazine executive editor Lori Majewski has recommended that Britney go on Oprah Winfrey's chat show to apologise for her recent behaviour.

Majewski said: "The public can be very forgiving and if she were to go on Oprah, the court of public opinion could quickly turn. A few tears and the words, `I'm sorry', can go a long, long way.

"But the ultimate key to the success of her future career is a new cleaned-up image and a hot single."