A legal battle by Gulf war veterans who claim they were made ill by the conflict is set to collapse.
Veterans believe vaccinations made them ill
The veterans' own solicitors say that, despite a publicly funded probe, they cannot uncover enough evidence that "Gulf war syndrome" exists.
Their finding is likely to mean that legal aid is withdrawn from the eight-year bid for compensation.
The National Gulf Veterans' and Families Association says there remains a case to answer, and plans an appeal.
Without legal aid, however, there is no way that the case can be pursued on behalf of more than 2,000 veterans.
The Legal Services Commission said a decision on the case would be reached by the end of the month.
Patrick Allen, from solicitors Hodge, Jones and Allen, said the government should now consider ex gratia payments to settle the issue.
He said that his team had examined a wealth of scientific research looking into evidence for Gulf War-related illness - but had failed to find enough to convince a judge of its existence.
He told BBC News Online: "We would be very surprised if this case could go ahead.
"I can't say it was a close-run thing - we just didn't have any convincing evidence.
"We have to prove the case - it is not for the government or MOD to disprove it. We have fallen at the first hurdle."
The problem for scientists is trying to establish a cause for the variety of symptoms reported by veterans.
Many of these are experienced regularly by the general population, and linking them directly to any particular exposure to chemicals or vaccines during the conflict - as has been alleged - is extremely difficult.
More than 2,000 Gulf War veterans in poor have already been awarded "war pensions" - but these are not of a high value, amounting to only £130 a week for those with the most severe disabilities.
However, as the "burden of proof" is reversed in pensions cases, with the MOD having to disprove the allegations, it has been easier for the veterans to win.
Shaun Rusling, chairman of the National Gulf Veterans and Families Association, told BBC News Online that a rift had already opened between his organisation and the solicitors handling the case.
"We have, for over a year, refused to meet with Hodge, Jones and Allen on the grounds of no confidence in the management of our case.
"We fully believe that there is a case to answer by the MOD and recent court cases by our members confirm this.
"Any decision to withdraw funding will be appealed."