Ehud Olmert pledged Thursday to step down immediately as Israel's prime minister after his party chooses a successor this month, shooting down speculation he would try to linger in office.
The announcement means that Israel could find itself racing to form a new government in as little as a week. And it raised new questions about Washington's goal of brokering an Israeli-Palestinian peace agreement by year's end.
Olmert, who is battling a corruption investigation, announced in July that he would resign after his Kadima Party chooses a new leader in a Sept. 17 primary. But some felt he was vague about the timing of his exit, raising speculation that he would try to hold onto power.
Addressing a Kadima Party meeting Thursday, Olmert said he never intended to delay his resignation. "As I have said before, immediately after the selection of a new chairman of Kadima, I plan to resign and recommend to the president to pick the new head of the party to form a government," he said.
But under Israel's complicated political system, Olmert could find himself in office well into next year, even if that is not his intention.
Olmert would stay on as a caretaker while his successor tries to form a new coalition. If the new leader fails, it would force the country to hold a general election a year and a half ahead of schedule. Coalition negotiations could last until next spring, and Olmert would remain in office until then.
Though Kadima will hold its primary next week, it could be forced to hold a second round the following week if none of the four contenders receives 40 percent of the vote.
Foreign Minister Tzipi Livni, Israel's lead negotiator in peace talks, and Cabinet minister Shaul Mofaz, a former defense minister and military chief, are the front-runners.
Opinion polls show a tight race in general balloting between Livni and hardline former Prime Minister Benjamin Netanyahu, whose election could set back the U.S.-sponsored Mideast peace drive.
With that in mind, both Kadima front-runners are expected to try to keep the current coalition intact. They might not succeed, however, because coalition partners are likely to push new demands for funds for pet programs or plumb Cabinet posts.
During this transition period, Olmert would find it difficult for him to push forward with his major diplomatic initiatives — peace talks with the Palestinians and separate, Turkish-mediated negotiations with Syria.
Opponents have already complained that the lame-duck Olmert has no authority to be negotiating such sensitive issues as he prepares to leave office, particularly in the circumstances surrounding his departure.
"There are no restrictions legally, but political and public pressure can prevent the government from functioning practically. Olmert knows this very well," said Avraham Diskin, a political scientist at the Hebrew University in Jerusalem.
In his Thursday speech, Olmert defended his negotiations with the Palestinians and Syria. He also said he would press for release of Sgt. Gilad Schalit, a soldier captured by Hamas-linked gunmen more than two years ago.
"Gilad is alive, and Hamas holds responsibility for his fate," Olmert said. "If a single hair falls from his head, Hamas will pay the full price." Talks mediated by Egypt have so far failed to produce an exchange. Israel has put together a list of hundreds of Palestinian prisoners it is prepared to release for the soldier.
For months, police have been investigating a string of corruption cases involving Olmert. In one, Olmert is suspected of improperly accepting cash and fancy gifts from a U.S. supporter. In another, he is suspected of submitting multiple bills for trips abroad, pocketing the difference or financing trips for relatives.
All the cases date back to periods before Olmert became prime minister in 2006. Olmert, who says he is innocent, has not been charged, though police investigators this week formally recommended he be indicted on bribery, breach of trust and money laundering charges.