A group representing hundreds of former military personnel is asking the High Court in Britain to rule on whether they're entitled to compensation for illnesses they say were caused by British nuclear weapons tests in Australia and the Pacific in the 1950s.
The nearly one thousand-strong group includes servicemen from New Zealand, Fiji and Britain.
During the three-week hearing, which began today, the British defence ministry is expected to argue it's too late for the claim to be heard.
The lawyer representing the servicemen, Neil Sampson, says the government changed its reasoning in the face of strong evidence.
"The Governments of this country, over the past 50 years have always said if you can prove that there is a link between the exposure and the diseases we will deal with the compensation claims, what is now happened is that their lawyers are saying, ah, sorry you are out of time."
Lawyer Neil Sampson.