By Caroline Briggs BBC News entertainment reporter

Radiohead were the first band to sign up for Help: A Day In The Life

The aim was to record the fastest-ever studio album to raise money for the charity War Child and draw attention to the horrors of the war in the Balkans.

Oasis, Blur, Suede, Manic Street Preachers, Radiohead and other big artists of the day agreed to give their time for free and record a track on the Monday for an album that would be in the shops by Friday.

It was a challenge that would pay off and become one of the highlights of the Britpop year.

Within a day of going on sale, 71,000 copies of Help! were sold and almost �2m was raised for War Child within three days.

In all, it took a mere six days from the album being recorded to it reaching the top of the album charts.

Fast-forward a decade and War Child has decided to do it all again.

While the names of the bands are different, those taking part are still among the biggest of the day.

Keane, Gorillaz, Kaiser Chiefs, Hard-Fi, Radiohead and Bloc Party are among those laying down a mix of old and new tracks.

While the focus of the world's attention has shifted from the Balkans to the conflicts in Afghanistan and Iraq, technology has changed too.

WAR CHILD In the last decade at least 1.6 million children have been killed as a result of wars A further four million have been disabled War Child works with children and communities blighted by war They include Rwanda, Sudan, Afghanistan, Angola and Iraq Money raised by the new album will be spent on material and psychological support and rehabilitation to children in war-torn areas

As the popularity of downloading music from the internet has soared, the aim of the new album - Help: A Day In The Life - is to produce the world's fastest-ever online download album.

Instead of the five days it took for Help!, the new album would take just 24 hours from start to finish.

The 20 bands and artists involved began recording their tracks at lunchtime on Thursday, and plan to continue until the same time on Friday.

War Child hopes to have the whole album ready for download on Friday afternoon.

War Child chief executive Mark Waddington admitted it was a "tall order".

"As a music fan, I know what the original Help album meant and I know what it achieved.

Oasis took part in the first Help! album during the height of Britpop

"It was my intention that any new album we made in 2005 should match up to the feats of the past.

"That's why we have set ourselves the challenge of remaking history and releasing the fastest album ever... again!"

Back in 1995, singer Neneh Cherry - who recorded 1, 2, 3, 4, 5 with Trout - was the most far-flung of those taking part as she laid down her vocals in a studio in Malaga, Spain.

While the Manic Street Preachers recorded their version of Raindrops Keep Falling On My Head in France, the other artists were dotted in studios around the UK, mainly in London.

This time, the artists are recording across the world.

Both albums

Gorillaz are in Hong Kong and Kaiser Chiefs will have three hours to record their version of I Heard It Through The Grapevine while on tour in Berlin.

Irish singer-songwriter Damien Rice is interrupting the recording of his second album in Dublin to record his new track, while Belle & Sebastian will record their track in Glasgow.

Others taking part include The Magic Numbers, Maximo Park, Mylo, The Zutons and the Mercury Prize-winning Antony and the Johnsons.

Radiohead and the Manic Street Preachers are the only artists who will appear on both albums.

Keane are patrons of War Child

In 1995, Radiohead recorded Lucky in a London studio as the other 19 tracks were being laid down elsewhere.

The following day masters were cut and flown to Blackburn where the CDs were made, and Holland for the cassette versions.

By Wednesday, the 300,000 copies were being manufactured and by Friday they were in record stores throughout the UK.

This time around things will be a little more slick.

After recording, the songs will be sent to a mixing studio in London. Within hours the entire album will be available for anyone in the world to download.

Not bad for 24 hours' work.