European Union leaders gathered for a second day of talks in Brussels at their annual spring summit, with nuclear safety expected to dominate Friday's conversation after they found common ground on economic reforms and Libya the night before, dpa reported.
The ongoing problems that Japan has faced at one of its nuclear facilities in the wake of a magnitude-9.0 earthquake and ensuing tsunami have led countries around the world to reassess their plants and have renewed a debate about their safety.
EU leaders have been consistent in expressing their sympathy with Japan, but have differed on what measures should be put in place as part of the lessons learned from the Asian country's troubles.
Ministers earlier this week agreed on the need for so-called nuclear reactor "stress tests" to ascertain the plants' earthquake and flooding risks, assess their cooling systems, emergency power supplies, ages and designs, and test the potential impact of man-made risks, such as terrorism or cyber attacks.
But EU members have been arguing over the stringency of the stress test criteria, with countries such as Germany calling for strict, binding measures - a stance that has been opposed by Britain in particular.
"It is not enough to handle the safety of nuclear power plants on the national level. It also has to occur on the European and international level," German Chancellor Angela Merkel said as she arrived for the second day of talks.
"I am very happy that it looks like we will come to comparable stress tests for nuclear power plants," she said.
But countries such as Finland have argued that there is no need for common EU regulations.
"Every country must be responsible for their own activity," Finish Minister of Economic Affairs Mauri Pekkarinen had said at the start of the week.
There have also been questions on who should carry out the tests. A draft of the summit conclusions calls for "a comprehensive and transparent risk and safety assessment" to be conducted by "relevant national authorities."
"It needs to be made clear that the safety tests are done by independent experts and not experts of the nuclear lobby," Luxembourg Prime Minister Jean-Claude Juncker said as he arrived on Friday.
Responsibility for nuclear safety standards rests with individual EU member states. EU Energy Commissioner Guenther Oettinger has noted that the stress tests would be an "optional system."
Fourteen countries in the 27-member bloc produce nuclear power, operating a total of 143 reactors.