Bulgaria will hold a referendum on the construction of a second nuclear power plant, parliament decided on Wednesday, eight months after the government scrapped a deal with a Russian firm to build one.

Voters will answer the question "Should Bulgaria develop nuclear energy by building a new nuclear power plant?" at a date during the next three months to be decided by President Rosen Plevneliev.

The referendum, the first in Bulgaria since the end of communism two decades ago, will also likely be a major issue in campaigning for general elections due to take place in July 2013.

The referendum was initiated by the left-wing Socialist opposition following the right-wing government's decision in March to walk away from a deal withRussian state-owned company Atomstroiexport to build Bulgaria a second plant, a 2,000-megawatt facility at Belene, on the Danube river.

The text stops short of mentioning Belene but any new plant is likely to be built there because European Union regulatory approval has already been granted for the site.

Bulgaria was forced to mothball four out of six reactors at its sole nuclear power plant, outside the northwest town of Kozloduy, because of safety concerns when it joined the European Union in 2007.

The two remaining reactors at Kozloduy, in service since 1987 and 1991 respectively -- and which suffer frequent technical problems, the latest just this week -- produce around 30 percent of Bulgaria's electricity.

Efforts to get the Belene project off the ground were plagued by severe delays, constant price haggling with the Russian side and the inability to attract private investment, prompting Prime Minister Boyko Borisov to pull the plug.

Atomstroiexport's subsequent decision to sue Sofia for one billion euros ($1.3 billion) in compensation at the Paris-based International Court of Arbitration prompted the government however to hint that it might revive the project.

A total of 38 percent of voters support building at Belene, 28 are against and the rest are undecided, a recent poll showed.

Experts warn that the referendum may fail to attract the necessary voter turnout to be valid, and critics have said that many voters lack the necessary specialist knowledge to be able to make an informed decision.