Tony Blair spoke of a peace plan emerging within days, and he and other Western leaders are hoping that a beefed-up UN force will receive backing tomorrow from a meeting in Rome of the US, Russia and countries from the Middle East and Europe. “What’s important is that we leave Rome with a concrete strategy,” Kofi Annan, the UN Secretary-General, said.

With the US and Britain leading calls for the creation of conditions that would allow a sustainable ceasefire, several EU countries showed their readiness to contribute to such a force, and the UN was ready to begin negotiations with individual countries if the conference tomorrow gives the go-ahead.

The idea will also be discussed at a conference of the Asian Regional Forum in Kuala Lumpur on Thursday and Friday to be attended by China, Russia, India, Australia and Japan, as well as Dr Rice and Javier Solana, the foreign policy chief of the EU. Western politicians clearly hope that some of those countries will provide manpower for a force that British officials say would run into the high thousands.

But diplomats accept that the force could not move into southern Lebanon without a ceasefire, and there are serious doubts that Hezbollah would agree to stop fighting if it knew that international troops were arriving to keep it at bay.

In Beirut yesterday Dr Rice told Nabih Berri, the Shia Muslim Parliament Speaker and Hezbollah’s de facto negotiator, that “the situation on the border cannot return to what it was before July 12”, the day that Hezbollah captured two Israeli soldiers.

She said that there could be no ceasefire before Hezbollah released the pair unconditionally and pulled back its forces about 20km (13 miles) from the border.

“If we have learnt anything it is that a peace will have to be based on enduring principles and not temporary solutions,” she said later, after her arrival in Jerusalem. But Mr Berri flatly rejected the terms, insisting that a ceasefire had to precede any talks about Hezbollah’s presence in the south.

British diplomats said that Egypt and Saudi Arabia would have a vital intermediary role, and Mr Annan said that Iran and Syria, Hezbollah’s main backers, would have to be involved. “You cannot disarm Hezbollah by force,” he said.

Israel initially dismissed the idea of an international force, but Amir Peretz, the Defence Minister, said that once the Israeli military had removed Hezbollah from the border his Government would be happy to see such a group move in to help the Lebanese army to deploy across southern Lebanon.

However, Israel clearly wants to wreak more destruction on Hezbollah before agreeing a ceasefire. One senior Israeli official told The Times that Dr Rice’s visit would provide a distraction from the humanitarian situation in Lebanon, while the protracted nature of her tour gave Israel another week to continue its military operations.

Dr Rice’s visit to Beirut was intended to show support for the embattled Lebanese Government. “Thank you for your courage and steadfastness,” she told Fouad Siniora, the Lebanese Prime Minister, as he kissed her on both cheeks. The Bush Administration announced last night a $30 million (£16 million) package of immediate humanitarian aid for Lebanon.

Mr Blair said that the key elements of the plan were an end to the fighting, the return of kidnapped Israeli soldiers and the buffer force. “What is occurring at the present time in Lebanon is a catastrophe,” he said.

Britain is unlikely to contribute to an international force because of its commitments in Iraq and Afghanistan, but Germany, Greece, Italy, France and Turkey have expressed interest.

The Israeli Government is sending Shimon Peres, the country’s elder statesman, to Western capitals to explain why Israel will not silence its guns.

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