Lithuanian voters on Sunday rejected plans to build a new plant to replace the Baltic state's lone nuclear power station, a Soviet-era facility shut down under the terms of its EU entry, though the result does not bind the government to act.

Almost 62 percent of voters cast "No" ballots in a referendum, while close to 35 percent backed the plan, partial figures from the national elections commission showed.

Turnout was over 50 percent, the level required for the plebiscite to be valid.

"I cast a 'No' ballot," said voter Lina Kacinksiene. "I'm against it for environmental, security and financial reasons."

Despite placing no legal obligation on the government, the result throws new doubt on an already-sluggish project because the referendum was held in tandem with a general election topped by left-wing parties who have faulted the project.

Anti-nuclear campaigners may well end up disappointed, however.

"We are for nuclear power," said Algirdas Butkevicius, leader of the centre-left Social Democrats, who came second in the polls to the leftwing populist Labour party with whom they are expected to form a coalition government.

The Social Democrats had pushed for the referendum, drawing Conservative government accusations of bad faith, given that they supported the project when they were in power before 2008 and even tried to get the old plant's closure date pushed back.

But Butkevicius said the problem was that current plans had been rushed through and made little technical or commercial sense, requiring a rethink.

Labour leader Viktor Uspaskich echoed that.

"This project must be carefully costed. Then we'll be able to see if it's economically viable, in which case I'll be in favour," he told reporters.

Despite rising global anti-nuclear sentiments following the 2011 tsunami disaster at Japan's Fukushima plant, Lithuania's centre-right government had pushed ahead with plans to build a new facility along with neighbours Latvia and Estonia.

"For the Baltic states building a new nuclear power station is very important, both from strategic point of view to have sufficient generation capacity, and also from an economic point of view," Conservative Prime Minister Andrius Kubilius, whose party came third in the election, told AFP ahead of the referendum.

One voter, 30-year-old Mindaugas who declined to give his last name, said the project was wrong on all counts.

"I don't believe Lithuania is able to build the plant, and will go bankrupt. I am also against having such a dangerous facility on Lithuanian soil. Thirdly, I don't believe electricity will be cheaper," he said.

Fifty-something Juozas Jurginas disagreed.

"I'm 100 percent for this new plant. Nuclear power is the best deal available. And the Chernobyl and Fukushima accidents aside, it's the safest form of energy relative to the quantity produced," he said.

Japan's Hitachi was tapped to construct the new plant in northeast Lithuania -- expected to generate 1,350 megawatts from 2020-2022, though final investment decisions were not expected until 2015.

The previous plant, of the same type as the one that exploded in Chernobyl in 1986, was built when Lithuania was still part of the Soviet Union.

Its eventual closure was a condition for Lithuania's 2004 admission to the European Union. Vilnius failed to convince Brussels to allow it to shift the December 31, 2009 cut-off date.

Since the old plant provided most of Lithuania's power, the nation of three million is now even more dependent on energy supplies from Russia, with which it has had rocky relations since independence two decades ago.

Lithuania's left-wingers had promised a sweeping review of the energy policy if they won power.

They said more should be done to insulate residential blocks in order to cut heating bills, a major strain on household budgets during the harsh Baltic winter.

They have also vowed to "reset" ties with Moscow, as tensions spike over alleged market abuses by Russian energy giant Gazprom, Lithuania's sole gas supplier.

Vilnius has sparked a major probe by EU competition authorities and filed a damages claim against Gazprom for almost $1.9 billion with international arbitrators.