Prime Minister Naoto Kan, under fire for his handling of Japan's worst disaster since the Second World War, has survived a no-confidence motion in his government but is likely to step down by end of this month.
Mr Kan told parliament yesterday that he will stay in power until he sees "progress" in bringing the Fukushima nuclear crisis under control and rebuilding the country's shattered North-east.
His announcement that he will quit once that task is achieved may have saved him from losing the motion after rebel lawmakers from his Democratic Party (DPJ) switched sides, leaving him with a comfortable win of 293-152 in Japan's 480-seat lower house. But it means he is living on borrowed political time.
The opposition immediately hailed the vote outcome as a victory. "We have forced the Prime Minister to announce he is resigning," said Sadakazu Tanigaki, leader of the Liberal Democrats. "It is the beginning of the end for the Kan administration."
The deal means that Japan again faces a political vacuum, and a summer general election, as it struggles to recover from the March disaster, which has left about 25,000 people dead or missing, more than 100,000 homeless and forced more than 70,000 people out of their homes near the crippled Fukushima plant.