Madonna, Robbie Williams and Sir Paul McCartney head the line-up for Live 8 - the biggest music event since Live Aid 20 years ago.

Bob Geldof has masterminded five free concerts to take place simultaneously in London, Paris, Berlin, Rome and Philadelphia on Saturday, July 2. The rock star turned anti-poverty campaigner said that the huge global event was the best chance to "finally put a stop" to world poverty.

He said: "At the beginning of the 21st Century, we have the opportunity to tilt the world a little bit on its axis in favour of the poor, and that’s not a difficult thing to do".

The shows have been timed to take place days before the start of the G8 summit in Gleneagles, Scotland, on June 6. Organisers of the deliberately-named Live 8 hope to persuade world leaders to write off the debt of poor countries, to double the international aid budget to £50 billion and to promote fair trade. Raising awareness rather than raising cash is the intention.

The massive concerts will be held at Hyde Park in London, the Eiffel Tower in Paris, the Brandenburg Gate in Berlin, the Circus Maximus in Rome and the Museum of Art in Philadelphia. A further event will be held in Scotland on the eve of the Gleneagles summit.

Around 150,000 music fans will attend the London concert alone. Billions more worldwide are expected to watch on TV.

The line-up for the British concert takes in the biggest names in music, with veterans of the original 1985 Live Aid event alongside the recording stars of today.

Robbie, Madonna and Sir Paul will be joined by Coldplay, Sir Elton John, Keane, Joss Stone and REM. Mariah Carey, The Cure, Dido, Annie Lennox, Muse, Razorlight, Scissor Sisters, Snow Patrol and U2 are also scheduled to appear.

The other concerts will see performances by Stevie Wonder in Philadelphia, Brian Wilson in Berlin, Duran Duran in Rome and Jamiroquai in Paris.

Other stars will be announced over the coming weeks - with the Spice Girls still rumoured to be staging a reunion.

"I spoke to them this morning and it’s looking very good," Sir Bob said. "There’s a lot of stuff they have got to sort through. They are trying to resolve differences of many years."

The 150,000 tickets for the Hyde Park gig will be made available through a special text lottery. At 8am on Monday June 6 a special multiple choice question will be broadcast on TV and radio, and will also be printed in newspapers. Members of the public will text in the answer and after seven days a computer will randomly choose the lucky winners, who will each receive a pair of tickets.

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