The secretary general of Japan's ruling Liberal Democratic Party, Mr Hiromu Nonaka, resigned yesterday, redoubling pressure on the beleaguered Prime Minister, Mr Yoshiro Mori, ahead of next week's cabinet shuffle.
Mr Mori urged senior colleagues, including Mr Nonaka - the LDP's second-ranking official who staved off a party rebellion last week - to stay on. But the powerful Mr Nonaka and the secretary of the Economic Planning Agency, Mr Taichi Sakaiya, signalled their departures.
"I am tired physically and mentally," Mr Nonaka (75) said. "I would just like to take a rest."
In September, Mr Nonaka indicated he would step down as LDP secretary general after a cabinet shuffle which Mr Mori is expected to announce on Tuesday as he seeks to shore up his crumbling support.
"As the party leader, I have repeatedly asked [Mr Nonaka] to stay in the position," Mr Mori said at a separate meeting with his coalition partners, according to the Chief Cabinet Secretary, Mr Yasuo Fukuda.
"But since he is firm in his intention of resigning, I cannot help but accept it," Mr Mori said.
Asked if Mr Mori plans to shuffle the cabinet on Tuesday, Mr Fukuda told a news conference: "The timing is around that day. We want the resignation of all the cabinet members early next week so as to form a new cabinet."
Mr Nonaka's departure was seen as a grievous blow to Mr Mori. The forceful official was one of four LDP elders who picked Mr Mori to replace the dying Mr Keizo Obuchi as Prime Minister in April.
Last week, Mr Nonaka played the leading role in rallying support for Mr Mori when a parliamentary rebellion by pro-reform LDP members led by Mr Koichi Kato collapsed.
"This undoubtedly will damage Mr Mori, who's already weak as Prime Minister," said a political analyst with UBS Warburg, Mr Shigenori Okazaki.
"Nonaka played the key role in rescuing the Prime Minister in the biggest crisis of this government," he said. "But he was saying even before the Kato revolt that he wanted to resign as he is getting old."
The LDP has unofficially nominated Mr Makoto Koga, the chairman of the party's Diet (parliament) Affairs Committee, as Mr Nonaka's successor, the Jiji Press news agency said.