FIVE peace activists arrested at RAF Fairford during the run-up to the Iraq war were attempting to stop what they believed would be a crime of aggression, the Court of Appeal heard yesterday.

Lawyers for the five argued that their belief that the war was a crime against peace provided them with a statutory defence to the criminal charges brought against them.

One of them, James Lewis QC, said the crime of aggression ranked alongside the other heinous international crimes of torture, piracy, war crimes and crimes against humanity.

As such, he said, it should be included in the definition of crime under Section 3 of the 1967 Criminal Law Act, which provided a defence to anyone whose alleged offence was comm- itted in the process of preventing a crime.

The Crown's argument that international crimes were not crimes under English law was misconceived, he added.

Mr Lewis was challenging a judge's pre-trial ruling that the five cannot plead the "illegality" of the war in Iraq as part of their defence.

He said: "They believed the lives and physical safety of the people in Iraq was in danger . . . and that the act of aggression was unlawful in international law."

Mr Justice Grigson, who is to preside at the pending trial at Bristol Crown Court, ruled at a preliminary hearing last month that the lawfulness of Britain's use of force in Iraq could not be examined or ruled upon by the court.

It is alleged that the protesters tried to break into RAF Fairford where US B-52 bombers were stationed, to disarm and ground the planes in three incidents before the start of the war in March of last year.

Phil Pritchard, of Campbell Road, Oxford, and Toby Olditch, of Billingdon Road, Oxford, deny conspiring to cause criminal damage at the base, and poss- essing articles with intent to destroy or damage property.

Margaret Jones, 55, of Burlington Road, Bristol, and Paul Milling, 58, of Bristol Road, Birmingham, are accused of conspiring to cause criminal damage to property.

Josh Richards, 30, of Easton, Bristol, is charged with attempted arson and having articles with intent to destroy or damage property. All five deny the charges and are on bail.

The hearing continues.