Voters in canton Vaud have come out against a proposal to keep a nuclear energy plant running indefinitely.
With 64 per cent against, they rejected plans to extend the licence for the Mühleberg plant, in neighbouring canton Bern. But the federal authorities still have the final say.
The plant, which supplies energy to the canton, has a licence to operate until 2012.
The energy ministry had been waiting for the outcome of the consultative vote before deciding whether to prolong the centre's life.
It is obliged to ask the cantons concerned by the decision: Bern and Solothurn have already said yes; Neuchâtel and Freiburg have said no. Vaud was the only canton to vote on the matter.
Nuclear power in Switzerland still divides opinion. Nearly three years ago, the Swiss government decided that two new atomic energy plants were needed to cover a predicted power shortfall after 2020. But any new plants need to be approved by voters, who have been sceptical over the issue in the past.
swissinfo.ch and agencies