Japan's prime minister has accepted responsibility for a projected crushing defeat in parliamentary elections on Sunday.
"The responsibility for this utter defeat rests with me," Shinzo Abe said at the ruling Liberal Democratic party's headquarters in Tokyo.
But he said he would not step down as his "task of nation-building has just begun"
Exit polls on Sunday indicated that the LDP would lose around half of the seats it was defending in the upper house of parliament, falling well short of the 64 seats it needs to maintain a majority in the upper chamber.
If the results are confirmed, the house will come under opposition control.
The more powerful lower house, however, where Abe's ruling coalition has an overwhelming majority, was not up for grabs, and the prime minister said he would stay in office.
'I will continue'
"I will continue to assume my responsibility as prime minister because my task of nation-building has just begun," a sullen-looking Abe said in a television interview on Sunday.
Previous prime ministers have resigned after upper house defeats that were less severe.
Abe assumed power in 2006 on a mission to build a nation "prouder of its past", but he has come under fire over a number of scandals, including the suicide of his agricultural minister and the mismanagement of Japan's pension system.
Analysts said that while the Liberal Democrats were worried that they did not have anyone better than Abe, it would be impossible for him now to govern.
"Abe is finished," said Gerald Curtis, a Japan expert at New York's Columbia University. "I think if he's smart, he'll quit tonight."
Curtis added that "it will just be more and more chaotic politically" the longer he stays.
Taro Aso, Japan's foreign minister, has made it clear that he would like to succeed Abe, but critics say he shares much of the same agenda and is prone to gaffes.
Opposition parties have seized on Abe's woes to try to win over traditional supporters of the Liberal Democrats, such as rural voters who feel left behind by free-market reforms.
Yukio Hatoyama, secretary-general of the Democratic Party of Japan, said: "We realised how strong people's dissatisfaction has been ... People have high expectations for us."
The opposition victory may make it harder for Abe to push through his agenda, although an opposition-led upper house can be overridden by the lower house, where Abe inherited an overwhelming majority from his predecessor, Junichiro Koizumi.
Abe was initially popular when he succeeded Koizumi about 10 months ago, but his approval ratings have since taken a nosedive.