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By Susanna Twidale
LONDON, March 25 (Reuters) - Britain is reviewing its nuclear cooperation agreement with Russian state firm Rosatom because of the Ukraine crisis, the Department of Energy and Climate Change (DECC) said.
The UK last November opened the doors to Russia to build nuclear power plants in the country by signing a pact with Rosatom to help the company prepare potentially to enter the British market.
But Britain's DECC said it had put the agreement under consideration as tension between the East and West mounts after Russian forces seized Ukraine's Crimea region.
"No decisions have been made on how this work will be taken forward, which is under consideration in the light of recent developments in Ukraine," a DECC spokesperson said by email.
Rosatom said on Tuesday it had no comment.
Under the deal, Britain's Office for Nuclear Regulation and the Environment Agency provided Rosatom with guidance on Britain's nuclear regulation.
Rosatom last year also signed a pact with Finnish utility Fortum and Britain's Rolls-Royce to work on having its reactors meet British regulatory standards.
A spokeswoman for Fortum said Russia had been a predictable and trustworthy partner.
"But since the political situation is evolving rapidly, it is not easy - if even possible - to draw conclusions on the future development of affairs," she said, without commenting further on the nuclear deal.
Rolls-Royce did not respond to requests for comment.
Britain is counting on the construction of new nuclear plants to replace ageing and polluting power stations that are closing over the coming years but it needs foreign investment to pay the huge upfront costs involved.
Last October, Britain signed a deal with France's EDF to build the UK's first new plant in 20 years. The government has also been courting other international investors such as China.
In what has become the biggest East-West confrontation since the Cold War, the United States and the European Union have imposed visa bans and asset freezes on some of Russian President Vladimir Putin's closest political and business allies.
They have so far held back, however, from measures designed to hit Russia's wider economy.
(Additional reporting by Svetlana Burmistrova in Moscow; Editing by Dale Hudson)