Britain is prepared to pay for access to the European nuclear organisation Euratom after Brexit, provided the country gets “a suitable level of influence” within it, Theresa May said.

The Prime Minister said maintaining “a deep science partnership” with the EU after the UK leaves in 2019 was in the interest of both Britain and the trading bloc.

In a speech at the Jodrell Bank Observatory in Cheshire, she said she was willing to discuss a deal with the EU as soon as possible over access to the agency, which Britain has been a member of since 1973.

She also signalled that current immigration rules for foreign students at British universities would remain in place post Brexit, saying the UK “will always be open to the brightest and the best researchers to come and make their valued contribution”.

Mrs May said: “The United Kingdom would like the option to fully associate ourselves with the excellence-based European science and innovation programme, including the successor to Horizon 2020 and Euratom R&T.

“It is in the mutual interest of the UK and the EU that we should do so.

“Of course such as association would involve an appropriate UK financial contribution, which we would willingly make. In return we would look to maintain a suitable level of influence in line with that contribution and the benefits we bring.

“The UK is ready to discuss these details with the (European) Commission as soon as possible.”

Euratom, formally the European Atomic Energy Community, is responsible for regulating the nuclear industry across the continent, disposing of waste, safeguarding the transport of nuclear materials, the mobility of workers in the sector, as well as nuclear research and development.

The organisation has been responsible for nuclear safety and security in Europe since 1957.

But Brexit legislation to leave the EU also means withdrawal from Euratom, a separate legal entity governed by EU institutions, because under the European Union Act 2008 the term “EU” includes Euratom.

Withdrawal from Euratom was announced in notes accompanying the bill to trigger Article 50 in January 2017.

At the time, broadcaster and physicist Brian Cox condemned a decision as “parochial idiocy”.

Theresa May visit to Macclesfield
Mrs May spoke to scientists at Jodrell Bank before her speech (Darren Staples/PA)

The desire to align the UK with Euratom was welcomed by businesses and trade unions.

Sue Ferns, senior deputy general secretary of the Prospect trade union, welcomed the announcement but said questions remained.

She said: “Firstly, how do they intend to turn the Prime Minister’s warm words on the contribution of EU scientists to the UK into concrete reassurances for the short term and eventually into a migration system that continues to allow the free exchange of people and knowledge across the continent?

“And on Euratom, if the Government can accept that an association for R&D is advantageous to the UK, why do they continue to insist that such an association is legally impossible in other areas, for example nuclear safeguards?”

Stephen Phipson, chief executive of manufacturers organisation EEF, added: “This clear commitment from the Prime Minister should provide reassurance to current programme participants negotiating their involvement in the next framework programme.”