The Bulgarian government has approved the construction of the country's second nuclear power plant at Belene on the shore of the river Danube.
Soviet-built Kozloduy: Two more reactors will be shut down
Two of the Kozloduy nuclear plant's six reactors have already shut down and two more will do so before Bulgaria joins the EU in 2007.
Two 1,000-megawatt reactors are planned for Belene. The project was begun in the 1980s but mothballed 12 years ago.
The government has estimated the extra costs to be 2.5bn euros (£1.7bn).
The decision was announced by Energy Minister Miroslav Sevlievski.
Nuclear power has had a controversial history in Bulgaria.
The Kozloduy power station, also on the shore of the River Danube, currently supplies more than 40% of the country's electricity.
The European Union has long expressed concern about safety at Kozloduy.
Bulgaria also exports electricity to many countries in South-East Europe.
Opponents of the construction of the new plant argue that the site is prone to earthquakes and that Bulgaria should improve its energy efficiency and invest in renewable energy sources instead.
Some economists have also questioned the wisdom of such a large investment.
A court case launched by environmentalists against the plant is still continuing. According to the plans, a tender will be launched in the next four weeks and construction should be completed by 2010.