UNITED NATIONS The international emergency response framework for dealing with nuclear power plant accidents needs to be reassessed and communications improved in light of the current crisis in Japan, the head of the UN agency that coordinates global nuclear safety said Monday. Nuclear power will remain an important and viable option for many countries as a stable and clean source of energy, IAEA Director General Yukiya Amano told an emergency meeting of his Board of Governors in Vienna, according to a news release issued at UN Headquarters in New York. He noted that the situation at Japans earthquake- and tsunami-stricken Fukushima Daiichi nuclear power plant remains very serious although we are starting to see some positive developments. Amano, who has just returned from a flying visit to Japan, said the current emergency response framework was designed largely in the wake of the 1986 Chernobyl disaster in the then Soviet Union, the worst ever civilian nuclear accident, and before the impact of the so-called information revolution.