The environment ministers from all 16 German regional states unanimously called on Friday for a temporary order to close seven nuclear power plants to be made permanent.
The federal government, which ordered a three-month shutdown of the seven oldest nuclear reactors in mid-March pending a safety probe after the Japanese atomic emergency at Fukushima, is to decide on their fate in June.
"The regions call on the federal government, in light of the reports from the reactor safety and ethic commissions, to enact legislation so that those nuclear reactors affected by the temporary moratorium can be permanently and legally removed from the grid," Sachsen-Anhalt environment minister Onko Aeikens said.
Germans have long been uneasy about nuclear safety and Chancellor Angela Merkel called for a rethink of her government's energy policy after the Japanese earthquake, vowing to close all nuclear plants as soon as possible.
She wants to build new conventional power plants and speed up development of renewable energy sources, such as wind power, instead.
The federal government will make its plans known by mid-June after reviewing reports it commissioned from the reactor safety agency and from a commission on ethics, specially set up for the purpose.
Germany has a total of 17 nuclear reactors but eight are off the grid.
In addition to the seven oldest closed by the government, the Kruemmel plant, in northern Germany, has been mothballed for years because of technical problems.
The state ministers, including both Merkel loyalists and opposition supporters, also urged Berlin to propose "an ambitious and realistic plan" for renouncing nuclear power altogether but they did not suggest a date.
Merkel recently suggested that 2022 was "a good time" for Germany to end nuclear power, backing a proposal by the Bavarian wing of her party.
