The British government has announced a new study into the health of veterans of atomic tests at Christmas Island in the 1950s.
The declaration comes just days before a judgment is expected in a landmark court case.
A thousand British, New Zealand and Fiji test veterans are suing the British government for negligence.
The veterans say they have suffered illnesses because of exposure to radiation.
They say these included cancers, skin defects and fertility problems.
In January, the High Court in London heard that researchers had found a small group of New Zealand test veterans had suffered genetic damage.
The Veterans Minister, Kevan Jones, says officials will work with veterans to take action to improve their health.
In a written statement, Mr Jones said the New Zealand study on genetic damage would be followed up.
He said this work would be under way before the end of the year.
The British opposition party, the Liberal Democrats, has welcomed the government's move.
But the party said the veterans needed proper recognition and compensation, not endless reviews and studies.