By Stephen M. Silverman
Updated September 16, 2003 01:00 PM

Though her new album, originally slated for release on Nov. 25, has been delayed until further notice, Britney Spears previewed a new song from it this past weekend in a surprise — and surprisingly steamy — performance in Las Vegas, reports MTV News.

The pop princess, 21, hit the stage in front of 1,800 people at Rain, inside the Palms hotel-casino, at 1 a.m. Sunday morning. According to MTV, the crowd was there to dance, not to see a performance. But then the dance music stopped and, as Rain co-owner Scott DeGraff told MTV News, everyone was bewildered when about half a dozen singers appeared on stage.

Then, when the dancers separated and Spears was revealed, the room went wild, said DeGraff.

“We’ve done a lot of crazy things,” he said. “This is going to be a tough one to top. There were an awful lot of celebrities there, from Dr. J to Michael Keaton, and they were all surprised. Only a very select group of people knew about it, the ones who had to pull it off.”

When all was sang and done, Spears performed 30 minutes of material, starting with “Me Against the Music” (her number from the NFL Kickoff Live concert), and unveiled “Breathe on Me,” both from her still-untitled new album. She reportedly also did a medley that included “I’m a Slave 4 U” and “Oops! … I Did It Again.”

Her props included an oversized black-and-white daybed lounger, and Spears and her dancers sexily shimmied toward it as they pretended to make out, said MTV. The routine ended with Spears exposing her red bra underneath her top.

“This wasn’t a Madonna situation,” said DeGraff said. “But there were simulated gyrations.”