An environment ministry decision to grant an unlimited licence to the Mühleberg nuclear power station has prompted mixed reaction.
The operators of the plant outside the capital Bern said they welcomed the move because it finally puts all five nuclear power stations in Switzerland on par with each other.
The Mühleberg facility became operational in 1972 and had a licence that was due to run out by the end of 2012. An application has already been handed in to built a new reactor in ten years’ time.
However, critics of nuclear power described the decision as irresponsible and scandalous. They pledged to challenge it in court.
The Swiss Energy Foundation said the Mühleberg plant had safety problems.
The technology used at the plant is also outdated according to the centre-left Social Democrats and the Green Party.
Last month voters in canton Vaud came out against extending the life of the plant beyond 2012.
The governments in four other cantons which are customers of the plant were divided.
swissinfo.ch with agencies