Nuclear worker members of the Unite trade union are set to be balloted on a new pension deal.

The agreement is for staff of the Nuclear Decommissioning Authority (NDA) at Sellafield, Chapelcross and across the UK.

It has the backing of the union's top officials and has already been approved by balloted members of the Prospect union.

Staff will move from their current final salary pension scheme to a career average scheme from April 2018 if the deal is backed.

The proposals set to be voted on are the result of negotiations between Energy Minister Jesse Norman, Unite and other unions.

Earlier this year there was a threat of strike action, but this was put on hold in February after talks with Mr Norman.

Unite national officer for energy Kevin Coyne said: “After more than a year of intensive negotiations, we believe that on the pension issue this is the best deal that can be achieved by negotiation.

“A significant achievement was to roll back the £620m savings demanded by the Treasury to a more manageable figure of £320m.

“The proposals remove the protections that the unions won for the workers on the denationalisation of the industry in the 1990 Electricity Act, but an amendment to the act will ensure the CARE (career average revalued earnings) scheme will inherit new protections.

“Unite is currently conducting a major briefing exercise to inform our members of the new proposals and what it means to their future retirement incomes.”

An NDA spokesman said: “Earlier in the year, the NDA ran a consultation process with all affected employees across its estate.

“Discussions with the trade unions on this issue are already well advanced - the unions seeking the views of their members is an important part of this process.”

Unite has 3,000 members who work for the NDA. Voting opens on June 12 and closes on June 30.