Cumbrian MP John Woodcock has said the loss of Euratom membership may be a "calamity" for Cumbria and put jobs in the county at risk.

His comments were echoed by fellow member from the county Trudy Harrison, who said the effects could be "economically crushing".

Both were speaking in a debate in the House of Commons about membership of Euratom – the European Atomic Energy Community, responsible for nuclear safety and security in Europe since 1957 – which is set to end as part of Brexit.

Last month's Queen's Speech announced a Nuclear Safeguards Bill to create a new regime for nuclear regulation but it has been claimed this is not enough.

Mr Woodcock, the Labour MP for Barrow and Furness, said he wanted to focus on NuGen, which has plans for a £10bn nuclear new build in Moorside, near Sellafield.

He said: "He (Richard Harrington, Parliamentary Under-Secretary of State for Business, Energy and Industrial Strategy, who attended the debate) will no doubt have spent a substantial part of his time so far in the Department trying to save the NuGen deal and find a new investor – almost certainly backed by a foreign government and foreign capital – to save a development that will create 21,000 jobs in Cumbria and potentially contribute up to eight per cent of the UK’s energy.

"I hope for a frank assessment of how the minister feels about the cloud of uncertainty over the industry, which has been created by the Government’s until now steadfast refusal to countenance remaining within a treaty that is working well, or to consider something sensible such as associate membership, and a seamless transition to that."

He added: "We know the difficulty behind the scenes in trying to get some countries, which I will not name, to consider rescuing the deal. Aside from any damage to UK energy security, the collapse in job prospects would be a calamity for the region.

"We need the Government to take an approach that gives the best chance of securing the investment at a difficult time. We have a new Minister and the Government apparently want to consider sensible clarifications and improvements to legislation: now is the time to change course."

Conservative Mrs Harrison, whose Copeland constituency includes both the Moorside site and Sellafield, added: "Ensuring continued membership of Euratom, or swiftly acting to develop an alternative, to be in place upon leaving the European Union or as part of a planned transition period, is vital.

"Because of the nature of the Sellafield site, Euratom safeguards are of key importance to its functioning. Every day, Euratom officials monitor activity on site and ensure that fissile nuclear material at Sellafield is in the right place and is being used for its intended purpose. Euratom owns cameras and other equipment and of course has the skills to carry out the work. If we leave, the ownership of that material and the skills will need to be replaced."

She also said the Nuclear Safeguards Bill did not cover all of the issues which needed to be addressed.

"Sellafield’s reprocessing facility has reprocessed fuel from several countries across the EU and further afield, including the United States and Japan," she said.

"The ownership of that material needs to be determined during the negotiation and new nuclear co-operation agreements to move materials overseas post-Brexit will need to be agreed and ratified."

Mrs Harrison added: "Whatever the decision taken, and whether we are in or out of Euratom in March 2019, safeguarding has to continue under international law. What cannot happen is a scenario in which new safeguarding measures and new co-operation agreements are not in place. Safeguarding is critical for the nuclear industry, and particularly for Sellafield.

"Without an approved safeguards regime, as well as new bilateral co-operation agreements, nuclear trade to and from the UK would stop, or at least slow down, which would be economically crushing for my constituency – a community that is home to thousands of nuclear workers and, indeed, the centre of nuclear excellence."

Mr Harrington said the Government was set to publish it position paper on Euratom "shortly" and that the Government was in negotiation with other nuclear powers around the world.

He added: "Nobody doubts the UK’s credentials as a responsible nuclear state, and everyone in the UK and elsewhere is keen to see that continue. The UK has been in the forefront of nuclear non-proliferation for 60 years. I have no doubt that we can bring these discussions to a satisfactory conclusion."

After the debate, Tom Greatrex, the chief executive of the Nuclear Industry Association, said: "While the industry has provided government with detailed information to help them understand the role of Euratom, it has also repeatedly been made clear to government that the industry’s preferred position is retain membership of Euratom. It is important now that the government ensures there is regular and constant dialogue with the industry, so they can understand the full consequences of decisions they will take over the period ahead.”