It's the endorsement Japan's government has been waiting for.br The United Nations' nuclear experts backing for stress tests designed to show the country's nuclear plants could withstand another disaster like last year's quake and tsunami.br The head of the International Atomic Energy Agency team in Japan is James Lyons.br SOUNDBITE: James Lyons, IAEA director of nuclear safety and security division and head of Japan Review Team, saying (English):br "We were able to give them some additional areas where they could improve their process, including using newer internationally accepted safety standards. They have, in their discussions with us, have indicated to us that they want to use those ne standards so we were confident that they would do a good job in their secondary assessment."br The 9 magnitude quake and subsequent, massive, tsunami in March 2011 wrecked the Fukushima Daiichi nuclear plant.br It's the worst nuclear crisis the world has seen in 25 years since the Chernobyl disaster.br The tests are computer simulations which evaluate a reactor's resilience to such events.br The IAEA's endorsement of the tests could help bolster government moves to restart other reactors.br Critics are questioning the validity of the tests.br They say they only simulate one natural disaster at a time.br They also suggest the tests don't reflect the risk of equipment failure and human error seen at Fukushima.