A MILE-LONG column of tanks and bulldozers was rolling into southern Lebanon last night after Israel’s security Cabinet approved a significant expansion of its four-week-old war to cripple Hezbollah.

Ehud Olmert, the Israeli Prime Minister, gave the go-ahead for thousands of Israeli troops to push across the border towards the Litani river, 20 miles (32km) into southern Lebanon. Troops were last night reported to be 6 miles inside the border. The operation could take 30 days, government sources said. The Cabinet was told the operation might cost the lives of 200 Israeli soldiers.

By approving the new offensive, the Israeli Government risks being accused of sabotaging the protracted attempts of the United Nations Security Council to agree terms for a negotiated end to the war.

However, those attempts appeared deadlocked last night, with France and the United States once again arguing over the draft resolution’s failure to demand an immediate Israeli withdrawal from Lebanon.

Tony Blair, on holiday in Barbados, spoke to President Bush and other world leaders yesterday, trying to find a compromise that would produce a speedy resolution. The Prime Minister was seeking a way for Israel to withdraw without enabling Hezbollah to re-arm.

The strongest indication of Israel’s growing impatience at its lack of military success came when the commander of Israeli forces in Lebanon was removed on Tuesday. General Udi Adam, who had been accused of excessive caution, was replaced by Major-General Moshe Kaplinski, the army’s deputy chief of staff.

Amir Peretz, the Defence Minister, had presented plans to escalate the war to the Israeli security Cabinet yesterday. Mr Olmert expressed some initial reservations, but, with Hezbollah firing hundreds of missiles into northern Israel, and the Israeli death roll rising, the hawks prevailed. The plan was approved by nine votes to nil, with three abstentions.

Mark Regev, an Israeli Foreign Ministry spokesman, said that the decision was necessary “in the absence of concrete steps coming out of New York”. But he added: “No one on the Israeli side has said ‘no’ to the diplomatic side. On the contrary, we are supportive of the process.”

Sean McCormack, the US State Department spokesman, said that Israel had a right to defend itself from Hezbollah. “The operating principle is that you don’t want to leave a vacuum in southern Lebanon. You don’t hand the keys back to the terrorists who started all of this.” But he added that the US was very concerned about the humanitarian situation: “Israel must take the utmost care in avoiding civilian casualties.”

Earlier yesterday, President Chirac of France had said that it would be immoral to abandon attempts to secure an immediate truce in Lebanon.

Responding to the Israeli announcement of a new offensive on the Hezbollah al- Manar television station, Sheikh Hassan Nasrallah, the Shia group’s leader, vowed that his fighters would “keep fighting to the last shot”, adding: “We will turn our precious southern land into a graveyard for the invading Zionists.”

He warned all Arab Israelis living in the Israeli coastal city of Haifa to leave so that they would not be killed by Hezbollah’s attacks. But he also sought to stir the diplomatic pot by claiming that Hezbollah fully supported a Lebanese plan to deploy 15,000 troops in southern Lebanon if Israel agreed to a ceasefire and withdrew its forces from the region.

Sheikh Nasrallah’s appeal is likely to be a destabilising tactic intended to increase tensions between Israel’s Jewish majority and its 1.2 million Arabs.

Many have already moved to safety, but some rejected the Shia leader’s call, fearing that it would jeopardise relations in Haifa, a city seen as a model of co-existence. Nabil Khoury, a Christian Arab resident, said: “This will only make the Jews think of us as traitors more than before. We have had enough problems so far.”

Despite four weeks of heavy air bombarments and the dispatch of 10,000 troops across the border, the Israeli military has failed to secure more than a handful of villages in southern Lebanon.

The Israeli Army said that 15 soldiers were killed yesterday and another 39 wounded in the bloodiest day of the conflict.

There were reports last night that members of Iran’s Revolutionary Guard have been found among Hezbollah guerrillas killed by Israeli forces in southern Lebanon.

The reports on Israeli television, citing diplomatic sources, said that the Iranians were identified by documents found on their bodies, but gave no further details. Hezbollah later denied the claims.

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