Janet Jackson apologised today for baring her breast to millions of viewers, and admitted she changed the performance after the final rehearsal.

"I am really sorry if I offended anyone. That was truly not my intention," the doe-eyed pop singer said in a videotaped statement released overnight.

"My decision to change the Super Bowl performance was actually made after the final rehearsal.

"MTV, CBS, the NFL had no knowledge of this whatsoever, and unfortunately, the whole thing went wrong in the end," Jackson said.

In a performance before nearly 100 million US viewers during Sunday’s American football championship, the singer Justin Timberlake tore at Jackson’s leather bustier, revealing her breast in an apparent "wardrobe malfunction".

Jackson’s spokesman said a red lace underlayer was supposed to have remained intact. Outrage and surrounding the prime-time over-exposure has fascinated the world for two days.

It has generated more internet traffic than the September 11 terror attacks, becoming the most searched event on the Lycos search engine.

"On Monday, Janet Jackson and the halftime show received 60 times as many searches as the Paris Hilton sex tape and 80 times as many searches as Britney Spears," said Aaron Schatz, survey chief of the internet portal Terra Lycos.

Mr Schatz noted that prior to this week, the most-searched event in the history of "The Lycos 50" survey over a one-day period was the September 11, 2001 terrorist attacks.

Despite the mishap, the organisers of the music industry’s coveted Grammy Awards, which will be broadcast live from Los Angeles on Sunday, said both singers would be allowed to appear on the show.

But CBS, the television network that also aired the Super Bowl, said it was adding an extra time delay to its Grammys telecast to allow it to "delete both inappropriate audio and video footage from the broadcast" if needed.

The Recording Academy’s Ron Roecker said that Jackson would present a Grammy statuette to a winner as scheduled and that Timberlake would perform as planned.

CBS faces a Federal Communications Commission investigation into whether the Super Bowl show violated decency laws, with potential fines of up to $27,500. If applied to each CBS station, the fine could reach into the millions.