The US state department has dismissed as “outrageous” a suggestion by Israel that it has been authorised by the world to continue bombing Lebanon.

“The US is sparing no efforts to bring a durable and lasting end to this conflict,” said spokesman Adam Ereli.

Israeli Justice Minister Haim Ramon made the suggestion after powers meeting in Rome refrained from demanding an immediate ceasefire.

UK PM Tony Blair has arrived in Washington for talks on the crisis.

His meeting with US President George W Bush comes amid growing pressure for the UK and US to join calls for an immediate ceasefire between Israel and Hezbollah.

Israel has carried out dozens of fresh strikes on Lebanon. Estimates of the number of people killed range from three to 13.

Two mortar rounds have hit a convoy of vehicles carrying civilians escaping the violence in southern Lebanon.

The BBC’s Jim Muir, who was with the convoy, said two people – a driver and a television cameraman in a German television car – were wounded when the rounds exploded next to their vehicle.

The convoy, organised by the Australian embassy, was returning to the port city of Tyre from the border village of Rmeish, where hundreds of people have been trapped by the Israeli offensive.

Our correspondent says the cars were clearly marked as a press and civilian convoy, and that individual journalists had been in contact with the Israelis who knew about the journey.

A BBC security adviser travelling in a car behind the German television car said he believed the mortar rounds had been fired from the Israeli side.

At talks in Rome on Wednesday, the US, UK and regional powers urged peace be sought with the “utmost urgency”, but stopped short of calling for an immediate truce. That prompted Mr Ramon to declare Israel had received “permission from the world… to continue the operation”.

But questioned by reporters on the sidelines of a summit in Kuala Lumpur, Mr Ereli said: “Any such statement is outrageous.”

The US has said a ceasefire is only worth it if it can be made to last. Mr Bush reiterated the US’s rejection of a “false peace” on Thursday evening.

But the BBC’s world affairs correspondent, Nick Childs, points out that Mr Bush also emphasised how troubled he was by the mounting casualties, a suggestion – perhaps – that he is increasingly conscious of the price Washington is paying for its closeness to Israel.

Air strikes

Some 425 Lebanese, the vast majority civilians, are confirmed killed in the 17 days of the conflict – but a Lebanese minister has suggested scores more bodies lie under the rubble, yet to be recovered.

Fifty-one Israelis, including at least 18 civilians, have been killed, mostly by rockets fired over the border by the Lebanese guerrilla group Hezbollah.

The Israeli assault began after Hezbollah captured two Israeli soldiers and killed eight in a cross-border raid on 12 July.

In the latest developments:

• A Jordanian man was killed and at least three other people wounded in one of several strikes in Kfar Joz, close to the southern Lebanese market town of Natabiyeh
• A Lebanese couple in Kfar Joz died when their bomb shelter collapsed on top of them, and at least three children were wounded
• There were multiple strikes on the Bekaa Valley to the east, on villages around Tyre, and roads in the south-east
• Sporadic clashes were also reported in Bint Jbeil, where Israel suffered its worst single losses on Wednesday
• At least three people were reported injured as Hezbollah rocket attacks on northern Israel continued. Kiryat Shemona was one of the towns hit
• Unarmed UN observers have been temporarily relocated from border positions in southern Lebanon to posts manned by the UN peacekeeping force Unifil. It follows the deaths of four UN observers in an Israeli strike on Tuesday

In Israel, few people still speak of being able to neutralise Hezbollah, our correspondent in Jerusalem Katya Adler says.

Instead Israel speaks of trying to establish a “secure zone” empty of Hezbollah fighters north of the border with Israel.

The Israeli government’s announcement that it is calling up three divisions of reservists – said to number between 15,000 to 40,000 – suggests it is preparing for the possibility of a protracted war, our correspondent says.

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