She ruled out a quick cease-fire as a "false promise" and defended her decision not to talk to officials from Hizbullah or Syria.
"Syria knows what it needs to do and Hizbullah is the source of the problem," Rice said at the State Department as she outlined US hopes for a diplomatic solution to the current crisis.
Rice said she was meeting not only with Israeli Prime Minister Ehud Olmert but also with Palestinian President Mahmoud Abbas as well as with allies at a gathering in Rome.
'Cease-fire return to status quo’
Asked why she didn't go earlier and engage in quick-hit diplomacy to try to end the death and destruction that has gripped the region,
Daniel Ayalon, Israel's ambassador to Washington, told The Associated Press that Israel would not rule out an eventual international stabilization force. But he said Israel was first determined to take out Hezbollah's command and control centers and weapons stockpiles.
He described it as a "mop up" operation, and said that Israel had no desire to repeat its 18-year occupation of southern Lebanon that ended in 2000.
"They overplayed their hand, they miscalculated," Ayalon said of Hizbullah militants based in southern Lebanon and supported by Syria and Iran.
"This is a war not of our choosing," he said. The flare-up in violence began after Hizbullah captured two Israeli soldiers last week.
Rice said the United States was committed to ending the bloodshed, but didn't want to do it before certain conditions were met. The United States has said all along that Hizbullah must first turn over the two Israeli soldiers who were captured and stop firing missiles into Israel.
"We do seek an end to the current violence, we seek it urgently. We also seek to address the root causes of that violence," she said. "A cease-fire would be a false promise if it simply returns us to the status quo."
Rice said that it was important to deal with the "root cause" of the violence, echoing what has been the US position since last week.
President Bush, asked what he hopes Rice will achieve on her trip, said he would discuss it with her when he returns to the White House on Sunday. He was speaking at a restaurant in Aurora, Colo., as he met with 10 members of the military who recently returned from Iraq.
Talking to reporters aboard Air Force One as Bush was en route to an appearance in Colorado, she said the idea was "to provide the president and Dr. Rice a chance to continue to strategize with a key partner in the region on a diplomatic solution that will address the root causes of violence and terror in the region."
Bush and Rice will meet at the White House Sunday with Saudi Foreign Minister Saud al-Faisal and Prince Bandar bin Sultan, chief of the Saudi National Security Council.
The plans emerged following two days of meetings in New York with United Nations Secretary General Kofi Annan and envoys he sent to the region this week. Although Annan called Thursday for an immediate cease-fire, that is opposed by the United States. The Bush administration says the United States and the UN agree on the wider diplomatic goals for the region.
The United States has resisted international pressure to lean on its ally Israel to halt the fighting. Rice was likely try to point the way to a relatively quick cease-fire, but not an immediate one. She is expected in Israel on Tuesday, Israeli officials said on condition of anonymity because the schedule was not yet confirmed.
Rice is also expected to meet with European foreign ministers and representatives from Arab nations that have been unusually critical of Hezbollah. That meeting would take place somewhere in the Mideast, but the location is not set.
Rice's mission would be the first US diplomatic effort on the ground since the Israeli onslaught against Lebanon began.
The Rice initiative likely would be designed to give the United States a major role in brokering peace there. She is not expected to try to get a signed deal during her brief visit, however, and she risks laying out the U.S. goals only to have either side refuse to bargain.
Annan outlined the basic terms of a proposed cease-fire and the longer-range goals to remove the Hizbullah threat in southern Lebanon in a speech on Thursday.
Hizbullah is an Islamic militant group that also exerts political control over southern Lebanon, overshadowing the weak democratic central government in Beirut. The UN and US plan for long-term stability would give international help to the Beirut government to expel Hizbullah and install its own Army troops, something it has been unable to do on its own.
Israel called up reserve troops Friday and warned civilians to flee southern Lebanon, as it prepared for a likely ground invasion to set up a deep buffer zone.
UN mediator Vijay Nambiar stressed the urgent need for "a cessation of hostilities" in Lebanon despite "serious obstacles" and appealed to Israel to allow humanitarian access to beleaguered civilians.
Nambiar, who led a three-member team sent by UN chief Kofi Annan to the region to assess the worsening Middle East crisis, spoke during a public debate of the 15-member Security Council on how to bring a quick end to the bloodshed in Lebanon and Israel.
Nambiar cited "serious obstacles to the achievement of a comprehensive ceasefire in the immediate future" in the deadly fighting between Israel and Hizbullah in Lebanon.
But he stressed that some form of "cessation of hostilities" as called for by Annan Thursday was "essential so that captives are protected, humanitarian access is assured, civilian casualties are dramatically reduced, and the political space is opened to negotiate a full and durable ceasefire.