WASHINGTON, July 28 — President Bush and Prime Minister Tony Blair of Britain said Friday that they would present a plan to end hostilities between Israel and Hezbollah at the United Nations next week as Secretary of State Condoleezza Rice headed into an urgent round of weekend meetings in the Middle East to hash out the details.
Facing pressure from Arab and European allies to end the violence, Mr. Bush and Mr. Blair, at a joint White House appearance, painted the broad outlines of a plan in which an international peacekeeping force would insert itself between the warring sides and help the weak Lebanese military take control of the southern region controlled by Hezbollah.
But aides acknowledged that the hard work of figuring out what Lebanon and Israel would accept, and how an international force would be composed, lay ahead.
Israel wants to weaken Hezbollah and push it well away from the border, and may not be ready to call off its campaign, especially when it has serious doubts that an international force would be strong enough to contain Hezbollah. And Hezbollah, which built its reputation on its willingness to fight Israel, has always rejected calls to disarm, and seems to have a flow of military and financial support from Syria and Iran.
The challenges of any cease-fire plan were evident during another day of heavy fighting that included ominous signs of potential escalation. Hezbollah fired a powerful long-range rocket that it said it had not used before.
It penetrated 30 miles into Israeli territory, and while a few other rockets have traveled that far, Israeli officials said the kind launched Friday can carry more than 200 pounds of explosives, making it much more powerful than the Katyusha rocket that Hezbollah has mainly used. Several were launched as part of a barrage of at least 100 rockets that pounded Israel on Friday.
Israel continued its own intensive airstrikes and artillery barrages in southern Lebanon, and warned civilians south of the Litani River to move north in a sign that it would move farther into Lebanese territory. At least 13 people were killed in the strikes, adding to a death toll of at least 400, according to Lebanese officials, who say most of those people were civilians.
The rising civilian death toll has placed added pressure on Mr. Bush from European and Arab allies who have called for an immediate cease-fire. But Mr. Bush has said that Israel cannot stop its attacks unless Hezbollah does first. Still, after a 90-minute meeting in the Oval Office, Mr. Bush and Mr. Blair voiced concern about mounting civilian casualties, and said they were eager to see the fighting end as quickly as possible.
“Our top priorities in Lebanon are providing immediate humanitarian relief, achieving an end to the violence, ensuring the return of displaced persons, and assisting with reconstruction,” Mr. Bush said.
But both reiterated their position that any cease-fire resolution must include a long-term plan to disarm Hezbollah and evict it from southern Lebanon. The Israelis, and the Arab world as well, have taken the United States position as a tacit go-ahead to Israel to continue its campaign.
A high-level administration official involved in the talks, who was given anonymity to discuss internal deliberations, said the United States and Britain had a plan that would play out over the next several days. He said Ms. Rice, who is expected to arrive in Jerusalem on Saturday, would try to obtain an agreement between Israel and Lebanon in which they state the need for the fighting to end and that lays out terms for ending it, though he did not elaborate on what those terms might be.
But the official said that a political agreement would not be possible unless both sides were convinced that the international force would be strong enough to hold the southern territory, protect Israel and help the Lebanese government wrest control of the area from Hezbollah. The United Nations will begin talks about the makeup of the force on Monday, though the official said it was almost certain that United States troops would not be part of it.
The official said that with those elements in place, the United States, Britain and others could push for a United Nations resolution calling for an end to the conflict in a way that ensured Hezbollah would no longer be in a position to hurl rockets at Israel, which would withdraw its troops from the area. Mr. Bush and Mr. Blair stressed their new round of diplomatic efforts to forge a consensus to end the crisis, a painstaking process that could give Israel more time to hack away at Hezbollah.
“This approach will demonstrate the international community’s determination to support the government of Lebanon and defeat the threat from Hezbollah and its foreign sponsors,” Mr. Bush said. “This approach will make possible what so many around the world want to see: the end of Hezbollah’s attacks on Israel, the return of Israeli soldiers taken hostage by the terrorists, the suspension of Israel’s operations in Lebanon, and the withdrawal of Israeli forces.”
Speaking in the East Room of the White House, Mr. Bush and Mr. Blair presented a united front as they pushed a position that was at odds with European and Arab allies who have been calling for an “immediate cease-fire.” Their appearance stood in stark contrast to a meeting in Rome on Wednesday in which Ms. Rice fought, successfully, with other world dignitaries over her insistence that a joint statement declare that the gathered nations would “work immediately” toward a cease-fire.
On the eve of Mr. Blair’s trip here, there was widespread speculation in the news media that the prime minister — who has paid a steep political toll for siding so strongly with Mr. Bush on foreign policy — would distance himself from the president by joining that call. But he stood right by Mr. Bush’s side as he has so many times. They cast the conflict in terms of the broader fight against terrorism — arguing that in Lebanon, the Palestinian territories and Iraq, Islamist militants were trying to beat back democracy.
“It’s a global movement, it’s a global ideology,” Mr. Blair said. “We’re not going to defeat this ideology until we in the West go out with sufficient confidence in our own position and say, this is wrong. It’s not just wrong in its methods, it’s wrong in its ideas, it’s wrong in its ideology, it’s wrong in every single wretched reactionary thing about it.”
The United States and Britain are hoping that a United Nations Security Council resolution will force Iran and Syria to tread carefully before rearming Hezbollah, even though an existing resolution calling for the disarming of Lebanese militias has not been carried out. The Bush administration is also hoping that an international agreement will convince Hezbollah that it cannot continue to function as a military organization.
But the strategy depends on a weak Lebanese government being able to stand up to Hezbollah and on Israel pushing Hezbollah out of southern Lebanon. And it assumes that a settlement can be reached without Syrian assistance, something few diplomats, except those in the Bush administration, think is possible. The administration does not talk to Syria; it withdrew its ambassador last year after the assassination of a former Lebanese prime minister. United Nations investigators have linked Syria to the killing.
United States officials hope that their main Arab allies — Egypt, Jordan and Saudi Arabia — can pressure Syria to distance itself from Iran and endorse the peace plan. Mr. Bush said, “My message to Syria is, become an active participant in the neighborhood for peace.”