Bulgarian Prime Minister Boyko Borisov said Friday he was considering pulling out of a deal with Russian nuclear company Atomstroyexport to build a new nuclear power plant at Belene on the Danube.

"We already told (Russian president-elect Vladimir) Putin that we want diversification (...) of the plant's ownership and that it should not be Bulgarian-Russian only," Borisov told BNT state television.

"For three years we have not found another investor, he said, adding that he was awaiting a report on the deal from from British banking group HSBC.

Russia's nuclear company Atomstroyexport, hired in 2006 to build the two 1,000-megawatt reactors for the new plant, already said it was ready to supply one of them.

And Borisov said Friday the government would pay for it.

Two Bulgarian ministers travelled to Moscow a month ago "to tell the Russians that we will not construct Belene but will pay for our reactor," Borisov said.

Borisov said Friday Bulgaria already paid two-thirds of the price of the first reactor, or about 1.38 billion leva (705 million euros, $923 million), and might install the unit at the site of its partially closed nuclear plant at Kozloduy.

But asked to confirm if he was dropping the project altogether, he said he would wait for the HSBC report and might propose a referendum.

Price haggling has seriously bogged down all progress on the deal in recent years, with Russia insisting it cost as much as 6.3 billion euros, while Bulgaria demanding a price of about 5.0 billion euros.

An inability to find a strategic Western investor to join the project and Sofia's serious concerns about the plant's economic viability have also fuelled talk about dropping the deal.

He cited lack of progress on Bulgaria's plans to diversify its energy sources as one of the reasons for the resignation of his Economy and Energy Minister Traycho Traikov late Thursday.

The premier named Traykov's 33-year-old deputy Delyan Dobrev as his successor.

Bulgaria is almost totally dependent on Russia for its supplies of natural gas and oil, while its sole oil refinery is owned by Russia's oil giant Lukoil and Russia supplies all of its fuel for the Kozloduy's two operational 1,000-megawatt reactors.