Rapper 50 Cent has cancelled a string of UK and European performances after his high-stakes show-down with Kayne West entered a perilous new phase.

Yesterday, the New Yorker was beaten to the number one spot on the UK album charts by rival rapper Kayne West. Although official sales figures are not out until Wednesday, West’s new release Graduation has reportedly also outsold ‘Fiddy’s’ album Curtis in the US.

A record-label founder and clothing designer as well as a rapper, 50 Cent, whose real name is Curtis James Jackson, famously vowed to quit his solo career should West out-sell him.

After sales figures began to surface 50 Cent lashed out, accusing West’s record company of buying up copies of Graduation, but today he went to ground, cancelling a string of UK and European concerts.

The rapper was due to perform at this week’s Mobo Awards and Vodafone Live Music Awards, in London, and was to play for an MTV show in Germany on Friday, but today pulled out of all three appearances. A spokesperson for the Vodafone awards said the rapper had given no explanation for the late cancellation.

Since West moved his record release date to September 11 to coincide with 50 Cent’s album launch, the American media has been consumed by the rivalry. At the MTV Video Music Awards last week, organisers engineered a stand-off by putting the pair onstage together to present an award. Meanwhile Rolling Stone magazine had the rappers pose eyeball-to-eyeball for the cover of this month’s issue.

But if it’s only an exercise in hype, 50 Cent has done a good job of convincing the public he’s serious. Last week a video interview posted on YouTube showed the former gangster considering bowing out of his rapping career.

“After a while it's not exciting. I'm not really excited to go sell a record. I probably won't even put another album out. If I do put it out, I probably won't travel to promote it. The actual release of this record wasn't pleasant for me," he said.

When asked if he felt "burned out," he replied: "Not burned out, I just feel like I don't wanna do it anymore. It's the first time I ever told people publicly. I've been feeling that way for a while."

Should he fall on his sword, it certainly won't be 50 Cent's darkest hour. He was raised in a rough area of the Bronx in New York, orphaned at 8, and a crack cocaine dealer by 12. In 2000, he was shot nine times but survived.

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