A coalition of groups opposed to the US-led invasion of Iraq says it intends to take legal action for "mass murder" against British Prime Minister Tony Blair and US President George Bush before the International Criminal Court (ICC) in The Hague.

"What has happened is the mass murder of 20,000 or so Iraqis," Chris Coverdale said, a spokesman for the Stop the War coalition, told Sky News.

"We have to ensure that Bush and Blair and all the others associated with that decision to attack and kill Iraqis are held to account for it."

Some 600 supporters of the coalition, which was formed in September 2001, met in London to prepare for a mass demonstration in the capital on March 20, the anniversary of the invasion of oil-rich Iraq.

The anti-war movement brought an estimated one million people to demonstrate against the war in London a year ago and up to 200,000 braved massive security to protest at a visit by Bush to London in November 2003.

Mr Coverdale said the coalition had asked police, the prosecution service and the nation's top legal official, Attorney-General Lord Goldsmith, to investigate the accusations.

He said that under the statute establishing the ICC, if such requests at the national level were refused, the movement was then "entitled to approach the prosecutor in The Hague to ensure and ask him to initiate an investigation and a criminal prosecution of the offenders".

The coalition's decision coincided with mounting pressure on Mr Blair to explain the basis on which the country went to war.

"The war with Iraq was illegal but, furthermore, crimes were committed," Mr Coverdale said.

"Therefore you want to ensure that people who have committed the crimes answer for them in court."

He said Stop the War was basing its position on articles in the United Nations charter forbidding war.

© 2003 Australian Broadcasting Corporation

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