JERUSALEM - Israel's foreign minister yesterday joined the growing ranks of senior politicians who have turned away from embattled Prime Minister Ehud Olmert, as expectations built that there soon will be new elections.

Tzipi Livni, a possible successor to Olmert and a fellow member of his centrist Kadima Party, stopped short of calling for Olmert's resignation. But she did say the party needed to prepare for a new vote and indicated it should first pick a new leader.

"I think the reality has changed since yesterday, and Kadima has to make decisions," Livni told reporters in Jerusalem. "I suspect that Kadima needs to start right away acting for every eventuality, including elections."

Unlike other top Kadima leaders who have voiced support for Olmert as he attempts to fend off corruption allegations, Livni pointedly refused. Instead, she said that it was necessary to "restore the trust in Kadima," and that the allegations against Olmert were a matter not just of legality but also of "values and norms."

Olmert, whose term is not up until 2010, has been besieged in recent days by calls for his resignation. The most prominent demand came Wednesday, when Defense Minister Ehud Barak threatened to force early elections unless Olmert steps aside. Barak's Labor Party is Kadima's largest partner in the fragile coalition government.

Olmert did not comment openly on Livni's remarks yesterday and has not spoken publicly about the scandal since American businessman Morris Talansky testified on Tuesday to having given him $150,000, much of it in cash. Talansky said that the money was supposed to be for political purposes but that he believed Olmert had used at least some on such luxuries as fine cigars and an Italian vacation. Olmert had earlier denied that he took any money for personal gain.

Despite the growing pressure, there has been no indication from Olmert that he plans to step aside. "We can't allow party politics to trump the legal process," said a senior official in Olmert's office. "The prime minister has said he will resign if an indictment is issued. But he's confident that will not happen."

Israeli officials with insight into Livni's strategy said that she was acting in coordination with Barak and that the two have concluded that elections are inevitable. "Their common interest for some time has been to topple Olmert," said one official, who would speak only on the condition of anonymity. "Now they see their opportunity. . . . They understand it's over for him, and they have to move."

Barak and Livni have tried to force Olmert's hand in the past, to no avail. They each called for his resignation after the botched 2006 Lebanon war, but Olmert refused.

Livni's comments yesterday seemed to acknowledge that Olmert has no intention of passing the baton to her, if he does ultimately resign. Despite sharing membership in Kadima, the two have been bitter rivals, and Olmert is believed to want to try to leave Kadima's leadership in someone else's hands if he is forced out.

Although Livni is popular nationwide, she could have trouble in a Kadima primary. At least four candidates could vie for party leadership, and Livni has done less work than some of the others to build a base among the party's rank-and-file. Livni would also face tough competition in the general election. Likud Party chief Benjamin Netanyahu and Barak probably would be contenders.

Any election would also probably put a temporary halt to U.S.-backed talks between Israel and the Palestinians.