(Writes through with new quote, background, paragraphs 10-17)
By Peter Laca
BRATISLAVA, Jan 10 (Reuters) - Slovakia will restart a nuclear power plant unit it shut down at end-2008 to comply with its EU accession agreement because cuts in Russian gas supplies threaten to cause power blackouts, officials said on Saturday.
Bratislava declared a state of emergency on Tuesday after the flow of Russian gas stopped, and the government said the 440 MW unit at the older nuclear power plant, Jaslovske Bohunice, had to be put into operation again to maintain the stability of the entire electricity grid.
"We are aware that this is a violation of the accession agreement, but this is happening at a time of crisis," Prime Minister Robert Fico told a news conference after the government made the decision at an extraordinary meeting.
"Damage from violation of the accession agreement is smaller than damage that would be caused by a collapse of the electricity system."
Fico said the unit should resume power production in less than six days, and would remain in operation until Slovakia had guarantees of "absolute stability" in gas supplies.
Under the state of emergency, the gas firm SPP, run by GDF Suez <GSZ.PA> and E.ON <EONGn.DE>, is reducing gas deliveries to large customers with annual consumption exceeding 60,000 cubic metres to a "safe minimum". It is maintaining full gas supplies to households, hospitals and schools from its reserves.
Gas-powered electricity generation is also affected by gas supply restrictions, which threaten the stability of the power grid, the cabinet has said.
"Few people are aware that we are close to a blackout," Economy Minister Lubomir Jahnatek told the same news conference. "Only a small malfunction ... and a blackout will affect a large part of Slovakia."
The EU accession agreement, setting terms for Slovakia's entry to the bloc in 2004, forced Bratislava to close another unit at the Soviet-designed Bohunice plant in 2006.
Leftist leader Fico had opposed the accession deal, agreed by the centre-right administration his government replaced two years ago, and reiterated on Saturday that the Bohunice facility met all safety standards.
"This unit was, and still is monitored by all major international institutions (active) in this area, and the reason for its closure was political," he said.
The gas dispute, which began when Russia and Ukraine could not agree on 2009 prices, has led to the worst ever disruption of Russian gas supplies to Europe and intensified calls for alternative energy sources.
The continent relies on Russia for a quarter of its supplies, and eighty percent of Russian gas to Europe is piped through Ukraine. Pipelines running through Slovakia move around 20 percent of EU gas consumption.
Slovakia's southern neighbour, Hungary, which relies on Russia for around 70 percent of its gas, has also said it needs to consider whether to build new nuclear power generating capacity.
Fico said on Saturday he had informed European Commission President Jose Manuel Barroso and other EU members of Slovakia's intention to reconnect Bohunice to the grid.
The European Commission, the EU's executive arm, has said it will consider the matter if Slovakia wants to restart the Bohunice unit. (Editing by Tim Pearce)