The Swedish parliament has approved the replacement of old nuclear reactors with new ones, marking a change in policy on nuclear power.
The plan, proposed by the government, passed narrowly by two votes.
In 1980, a Swedish referendum decided to phase out reactors by 2010, although the target was later abandoned.
Sweden's 10 reactors, at three power stations, supply as much as half of the country's electricity.
The plan allows for new reactors to be built at the same site as the country's existing plants, but forbids the approval of new sites. The number of reactors is not allowed to exceed 10.
It passed by 174 votes to 172 against, with three MPs absent.
The centre-left opposition said they would rescind the law if they win the next election, due in September.
"Of course we will tear it up," said Tomas Eneroth from the Social Democratic Party.
Environmental group Greenpeace said the move was "irresponsible".
"The members of parliament show they do not take the environmental risks posed by nuclear power seriously, and that they do not trust in the enormous potential there is for Swedish renewable energy," Greenpeace spokesman Ludvig Tillman said.
Meanwhile, 29 activists appeared in court on trespassing charges after being arrested on Monday for allegedly breaking into the Forsmark nuclear power plant.
The group, who include protesters from Britain, Germany and Poland, had been calling for parliamentarians to vote against the proposal.