The group, who star in top-rated BBC One children's show Miami 7, hit the top spot with their heavily-promoted single Bring It All Back.

Fuller, who guided the Spice Girls to stardom before they sacked him, said he was thrilled with the number one.

"I started working on the idea of S Club 7 literally the day after I parted company with the Spice Girls," he said.

"It is so exciting to start the project off with a number one television show and now a number one single.

The Spice Girls are said to have made �6m each under Simon Fuller

"They are fantastic kids and the future looks bright."

The group were also delighted with their chart triumph.

Jon Lee, 16, said: "This whole week has been like waiting for exam results to come through, and it is like we have been given an A+ for everything."

Fellow group member Paul Cattermole, 22, said the news was "shocking".

"The girls are crying, but the boys are on top of it," he added.

S Club 7 saw off competition from Madonna, whose single Beautiful Stranger, taken from the soundtrack to the new film starring spoof spy Austin Powers, reached number two.

Three other Simon Fuller-managed acts also feature in the Top 40. Boy band Another Level are at number 11, Chicane are at 13, and guitar-wielding girl group 21st Century Girls are at 31.

But one of Fuller's former charges, former Spice Girl Geri Halliwell, fared less well in the charts.