The cases have raised the prospect that a Gulf War syndrome "mark 2" is emerging among troops involved in the US-led campaign to topple former Iraqi president Saddam Hussein.

The four soldiers, who have ailments ranging from depression to eczema and breathing problems, were among 45,000 British forces offered a cocktail of vaccines to protect against chemical and biological attack.

Solicitor Mark McGhee, representing the unidentified four, told BBC radio: "I personally have dealt with well in excess of 400 Gulf War One veterans.

"The symptoms which these individuals are experiencing are identical to those of the individuals I represent in relation to the first Gulf War conflict," he said.

McGhee said that soldiers should not have been given multiple vaccinations in one day.

"In relation to this particular (Iraq) conflict, it is my understanding that specific guidance was given to medical officers that these inoculations were not to be administered on a multiple basis," he said.

He added that all four soldiers had already been discharged from military service.

The British government has never accepted the existence of Gulf War syndrome, which was reported by troops who fought in the 1991 war that forced Iraq out of Kuwait.

This position is at odds with veterans' conviction that a range of physical and psychological ailments are connected to their service in the Gulf War.

A number of possible explanations for Gulf War syndrome have been put forward, including exposure to depleted uranium munitions or the side effects from the various vaccinations troops were given.

According to a recent press report, a government-funded scientific study by the Medical Research Council has concluded that Gulf War syndrome does not exist.

WAR.WIRE