Britney Spears raunchy Femme Fatale tour has apparently run out of steam in Britain, forcing promoters to slash ticket prices to fill a hall in Birmingham, an industrial city in the UK midlands.

The show is scheduled for Oct 30, but so far only about half the tickets to the 16,000-seat hall have been sold, according to London’s Daily Mirror.

The show is one of eight UK dates and was expected to sell out.

Ticket prices have been cut roughly in half. They originally were selling for $88, but are now being offered through special promotions for $48, and still aren’t moving.

Check out Britney’s photos; click to enlarge.

Promoters claim the cut-price deal was “segmented marketing to reach new consumers.”

“Offering a deal on Groupon is not a reflection of the quality or status or sales of a show,” said a spokesperson for Live Nation, the concert promoter.

A ticket seller, however, begged to differ. “It’s probably about half-full. There’s good availability,” he told the newspaper.

In addition to the price cut, discount site Groupon is offering a buy 10 tickets and get two free tickets deal.

Live Nation partnered with Groupon for the tour and has sold 18,000 tickets at discounted prices for 15 of the first twenty-four dates, according to VH1.

The economy could be playing a role. Britain, like the United States is suffering from high unemployment.

The tour got off to a rough start. It’s her first in two years, following her 2009 Circus tour. Britney, 29, hit the road weighing a hefty 155 pounds.

In an early Los Angeles outing, her dance moves were good, but not spectacular and at times she wore skimpy bikini costumes that revealed her tummy rolls.

When she sprawled on the floor, for a fleeting moment, it was anyone’s guess if she would be able to get up gracefully on her own.

Music critic Jim Harrington of the Oakland Tribune called the show “a mess pretty much from start to finish.

“The theatrics are awkward and confusing, the dance routines are numbingly bland and old-hat, the song selection is weak and misguided and Britney’s star power, so blinding on tours past, is remarkably dim,” he wrote.

But Britney has picked up her pace since then, and has been looking much fitter.

Rolling Stone magazine, in a sugary review, called the tour one of “possibly her flashiest, fastest moving, and most entertaining production yet.”

Just to prove she still has it, Spears danced to most of original choreography from an earlier tour for her hit song, “I’m a Slave 4 U.”

Spears has had two children, Sean Preston, five, and Jayden James, four, with ex-husband Kevin Federline.

Check out her photos and video.