A veteran of Allied atomic bomb tests is the first British soldier to win compensation from the US government over Christmas Island nuclear testing.
Roy Prescott wants a public inquiry in to the nuclear tests
Roy Prescott of Burton-upon-Trent, Staffordshire has terminal lung cancer.
The US government has agreed to pay £40,000 under the US Radiation Exposure Compensation Act for his illness following the nuclear tests.
But the Ministry of Defence (MoD) said there was not enough evidence the tests caused the 66-year-old's illness.
In 1962, he was on national service and watched 36 nuclear tests in 11 weeks whilst on Christmas Island in the South Pacific.
'Cold war casualty'
Mr Prescott's rare type of lung cancer is a form of the illness which can be caused by exposure to radiation.
He said it was the overwhelming evidence and research in the US which had led to the compensation payment.
The MoD has refused his application for compensation, turning down his claim for an enhanced war pension.
Mr Prescott said: "I am a casualty of the Cold War and whilst I am pleased the I am receiving compensation and recognition from the US government it galls me that the British government continues to fail in their duty of care towards me and thousands of other nuclear test veterans."
He called on the prime minister to apologise for the suffering inflicted on nuclear test veterans and to carry out a full public inquiry in to the matter.
An MoD spokesman said: "The US compensation scheme does not require claimants to show that their illness was as a result of service.
"The UK government, however, does ask those claiming compensation to show a reasonable link between their service and their illness.
"Unfortunately there is insufficient evidence to indicate that Mr Prescott's illnesses are attributable to his participation in these tests."