The group that brought the world tracks like "Whole Lotta Love", "Kashmir" and "Stairway to Heaven" reunited five years ago at London's O2 Arena for a tribute gig to Ahmet Ertegun, the founder of Atlantic Records which signed Led Zeppelin in 1968.

It was one of the few times the band performed together since breaking up following the death of drummer John Bonham in 1980, and sparked frenzied speculation that a lucrative reunion tour could be on the cards.

That has failed to materialize, and at a press conference to promote the new video of the 2007 gig, called "Celebration Day", lead singer Robert Plant, guitarist Jimmy Page and bass/keyboard player John Paul Jones all refused to be drawn on future plans.

Asked whether they might consider reuniting, Page, considered one of the greatest guitarists in rock history, replied: "Can I ask you a question? You've all been to see the film. Did you enjoy it?"

From a mostly partisan crowd of journalists and fans, the answer was in the affirmative. "Then we've done our job," added the silver-haired 68-year-old.

When a reporter called out would Led Zeppelin "do it again", Plant simply replied: "With you?"

Their non-committal answers will mean the guessing game over one of the most eagerly awaited reunions in rock is likely to continue for some time to come.

Celebration Day, directed by Dick Carruthers, is a two-hour film featuring all 16 tracks of the band's tribute gig, starting with "Good Times Bad Times", taking in "Dazed and Confused" and "Whole Lotta Love" and concluding with "Rock and Roll".

When tickets went on sale, an estimated 20 million people applied for 18,000 places, underlining the level of pressure the band has come under to play together more regularly.

"HE DROVE US"

On drums in the place of Bonham was his son Jason, a musician in his own right, who was praised by Plant and Page.

"It was appropriate and it was wonderful and also his vigor was so fantastic too," said Plant. "He drove us, you know. It was peculiar and strange at times, but at the same time it was very rewarding for all of us."

Plant recalled playing with Jason Bonham previously.

"We played with him before at his wedding," he said. "Sadly he decided to go to bed during the wedding reception, and because I was ... a friend of the family from way back I was the one who had to go up to his room and get him to get out of bed."

The long-haired lead singer admitted he had been reluctant to perform Stairway to Heaven, one of Led Zeppelin's most popular tracks, and arguably its most obscure in terms of the meaning of the lyrics.

"I struggle with some of the lyrics from particular periods of time," he explained. "May be I was still trying to work out what I was talking about ... Every other fucker is."

All three band members expressed a sense of relief when the O2 concert was over.

"Everybody's eyes are on us waiting for it to go not so much right as wrong," said Plant, adding that the band hugged each other when the concert was over.

Page recalled a "massive" party after the show, but the group itself "sort of disappeared into the ether."

He added that "there might have been a handful of fixes" to the sound in the film. "The concert was what it was," said Page. "There was very little that needed to be messed about with because we'd really done it well in the first place."

Jones, a man of few words when it comes to the press, was asked why Led Zeppelin had taken five years to produce a movie based on the concert.

"Five years is like five minutes in Zeppelin time," he said.

* Celebration Day will be shown at select movie theatres on October 17 and is available in video and audio format on November 19.

(Reporting by Mike Collett-White, editing by Paul Casciato)

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