Union leaders representing thousands of nuclear workers are to discuss calling a strike ballot in a row over pensions.
The unions said 16,000 workers at 19 sites face cuts under plans by the Nuclear Decommissioning Authority to make savings of £660 million. This includes sites in Essex and Suffolk.
The unions said the Government's expectation is that the final salary pension schemes in place across the NDA estate will be reformed by April 2018.
Kevin Coyne, Unite national officer, said: "We are urging all our members working for the Nuclear Decommissioning Authority (NDA) to resist this proposed Treasury-led 'raid' on their pensions - if it is allowed to go-ahead thousands of workers will see their retirement incomes slashed by thousands of pounds."
But a Nuclear Decommissioning Authority spokesman said:"Government policy is that all public sector final salary pensions schemes should reformed by 2018, and four million public sector workers have already moved to new pension arrangements.