Rachel Reeves has urged the government to provide greater clarity about its plans for civil nuclear power if the UK leaves the EU without a withdrawal deal.

The chair of the House of Commons Business, Energy and Industrial Strategy committee has written to Richard Harrington, who has responsibility for the nuclear industry in his portfolio as minister for business and industry, for more details about the government’s post-Brexit plans for the nuclear industry.

In the letter, Reeves acknowledges indications of progress on the civil nuclear relationship between the EU and the UK regarding issues like safeguards and trading arrangements.

The government passed a bill last year outlining plans to create a new safeguarding regime for nuclear material and labour once the UK has to leave its existing arrangements under the Euratom treaty.

The letter seeks more detail on the plans that the government is making to ensure that the civil nuclear sector can continue to function after next March if parliament has been unable to secure a broader separation agreement and whether a side-deal with Euratom is being pursued.

She also quizzes Harrington on whether the UK has received any signals from Euratom about whether it will be possible to maintain the “close association” that the government has said it wanted with the EU-wide nuclear co-operation arrangement.

Reeves also asks whether the government has made any arrangements to overcome possible hitches in the nuclear new build programme if the upcoming migration white paper inhibits the inflow of the migrant labour which has been “essential” for such projects.

Reeves said: “In the event of no deal and no transition period, the ongoing operation of the UK’s nuclear power stations could be put at risk. The government needs to spell out what it is doing to ensure that nuclear power stations continue to function from 29 March 2019 and whether it will seek a separate deal with Euratom in these circumstances.

“The government also needs to be clearer about its plans to facilitate the building of construction of major facilities such as Hinkley Point C if restrictions on migrant labour are introduced in the future.”