BRATISLAVA, Slovakia (AP) -- Slovakia's populist Prime Minister Robert Fico said Tuesday his government has approved an agreement with the United States to build an additional nuclear reactor.

Fico announced the multi-billion-dollar deal during a speech at an annual nuclear conference in the Slovak capital. He said that the new reactor will be built at the existing nuclear plant in Jaslovské Bohunice in western Slovakia, will have an output of over 1,000 megawatts and be fully owned by the state.

It was unclear when the two governments will sign the deal.

Fico didn't gave more details but his government had approved a plan last year for a 1,200-megawatt nuclear unit at the site where the dominant utility Slovenské Elektrárn? (Slovak power plants) currently operates two nuclear units. The cost of the project was estimated to reach up to 15 billion euros ($17.5 billion).

The government originally planned to find the builder in a public tender but recently said it was negotiating a direct deal with with U.S. company Westinghouse.

Slovakia heavily relies on nuclear energy and currently generates over 80% of its electricity at two nuclear plants.

The Slovak plan reflects recent nuclear expansion in Central and Eastern Europe. The neighboring Czech Republic has signed a contract with Korea's KHNP to build two more nuclear reactors. Poland struck a deal with Westinghouse to build its first nuclear power plant, while Russian energy giant Rosatom is set to build two more reactors in Hungary.