* Commission cannot force states to apply recommendations
* Says expects to propose new safety law next year
* Nuclear stress tests should not be a "one-off" (Adds reaction)
By Barbara Lewis
BRUSSELS, Oct 4 (Reuters) - Nuclear regulators and operators should act now to improve safety at nuclear power plants, the EU energy commissioner said on Thursday, following a series of inspections across the European Union.
The nuclear stress tests, carried out in the aftermath of the Fukushima disaster, found safety improvements costing anywhere between 10 billion $12.90 billion) and 25 billion euros were necessary in European plants, according to a draft seen by Reuters earlier this week.
"Nearly everywhere there is major potential for improvement," Energy Commission Guenther Oettinger told reporters.
"We therefore think that we should talk together with operators and regulatory authorities to act rapidly so that the highest possible standards can be guaranteed very soon."
In addition, he confirmed the Commission would be proposing new laws earlier next year, including on insurance and liability.
One of the lessons of Fukushima was that two natural disasters could strike at the same time and knock out the electrical supply system of a plant completely, so it could not be cooled down.
The stress tests endeavoured to protect against any repeat of that series of events by establishing whether nuclear plants can withstand natural disasters, aircraft crashes and management failures, as well as whether adequate systems are in place to deal with power disruptions.
Among the findings were that on-site seismic instruments should be installed or improved in 121 reactors.
In addition, 24 reactors did not have a back-up emergency room in case the main control room became uninhabitable.
Because EU authorities do not have power to determine the energy mix of member states, the stress tests were voluntary, but Oettinger said they would not just be "put in a drawer".
"We are at the beginning of a new European safety dynamic," he said.
He confirmed the Commission would follow up with legislative proposals early next year to enhance safety. The proposals would include insurance and liability, but Oettinger said it was not yet clear what that might mean for electricity bills.
Austria, which banned nuclear plants in 1974, said the stress tests were "good, but not good enough".
"Our demand is very clear: retrofit nuclear plants or shut them down," Austrian Environment Minister Niki Berlakovich told reporters in Vienna, referring to the possibility of adding safety meaures.
Green member of the European Parliament Rebecca Harms said the stress tests report had dodged the tough questions.
"One thing seems clear: this exercise has been orchestrated to cause as little stress to the nuclear industry as possible," Harms said in a statement.
Asking about possible pressure from member states to change the report, Oettinger told reporters there had been "absolutely no political influence whatsoever".
$1 = 0.7751 euros Additional reporting by Michael Shields in Vienna, editing by William Hardy