Japanese nuclear power plant operator TEPCO expects to stop pumping radioactive water into the ocean on Monday, days later than planned, a step that would help ease international concern about the spread of radiation from a smashed nuclear plant.
Prime Minister Naoto Kan's Democratic Party was likely to be punished at Sunday's local polls for his handling of the massive earthquake and tsunami that ravaged Japan's north-eastern coast on March 11, killing 13,000 and triggering the world's worst nuclear accident since the 1986 Chernobyl disaster.
China and South Korea have also criticised Japan's handling of the nuclear crisis, with Seoul calling it incompetent, reflecting growing international unease over the month-long atomic disaster and the spread of radiation.
Japan is struggling to regain control of the Fukushima Daiichi nuclear plant that was damaged by the magnitude 9 quake and 15 metre tsunami.