"I have failed to live up to your expectations and I have done irreparable damage to the party," he said in a news release addressed to DPP members. His wife, Wu Shu-jen, was also handing in her resignation, the statement said.

Chen said he would still accept investigations by party organizations and by the judiciary. Later yesterday, cable station ETTV reported that Chen was being questioned by the Supreme Prosecutors Office Special Investigation Unit.

Chen issued the news just before the DPP's Central Standing Committee began a special meeting to discuss the former leader's fate. DPP chairwoman Tsai Ing-wen (蔡英文) later told reporters the party respected Chen's decision and was willing to accept it. But she added he had "the right and the duty" to explain his family's financial dealings.

Earlier yesterday, Tsai apologized to society and to party supporters, while promising there would be no cover-up. She said a party anti-corruption committee had decided to start up an investigation into Chen's money.

Anger within the DPP had reportedly been building up since Chen's news conference Thursday, with party supporters calling in to the headquarters with messages of protest, local cable stations reported.

The DPP's Legislative caucus cancelled its regular daily news conference, while prominent lawmakers were reticent to voice an opinion on the matter.

Former legislator Lin Cho-shui (林濁水) said the DPP should break off its links with the former president. Another former lawmaker often critical of DPP policies, Lee Wen-chung (李文忠), said the party should suspend Chen's party rights and investigate him. If it was shown the problem was entirely Chen's and his family's, the party could still escape unscathed, he said.

The DPP's Taipei chapter later recommended the expulsion of Chen's son and daughter-in-law.

In a news release yesterday morning, the former president mentioned for the first time that the amount wired overseas by his wife totaled US$20 million. The funds were surplus money from his election campaigns, Chen said. The former president had been criticized for not mentioning any figures at his Thursday news conference.

Chen still denied there was money laundering involved. His statement said the funds had traveled through three banks not to evade detection, but because of a change of personnel at the banks. He confirmed that the funds were to be used for public and charity purposes, including Taiwan's diplomacy and aid to the underprivileged.

Government officials said Taiwan was fully cooperating with Switzerland in the investigation of the funds.

Justice Minister Wang Ching-feng (王清峰) and Taipei Prosecutors Office spokesman Fred Lin (林錦村) said separately yesterday a prosecutor traveled to Switzerland earlier this month with information requested by prosecutors there.

The Supreme Prosecutors Office Special Investigation Unit said yesterday that Chen Chih-chung and his wife left Taiwan last Saturday, August 9. Since neither has been charged with any crime, they have not been barred from leaving the country, unit spokesman Chu Chao-liang (朱朝亮) told reporters yesterday.

The ruling Kuomintang said Chen was trying to push responsibility away to his wife. KMT lawmaker Wu Yu-sheng (吳育昇) called for the former president's immediate arrest and for a thorough investigation into all his relatives and their bank accounts.