"The more time that passes, the more the slicks are dispersed by the wind and the currents," he added.

Naim said that unless the slicks are dealt with while they are still at sea, "the coastline will inevitably be soiled again, even if it has already been cleaned up".

Syrian officials said on Sunday that a new oil slick had reached its shores after initial pollution at the end of July, caused by Israeli air strikes in the middle of the month against the Jiyeh power station 30 kilometres (19 miles) south of Beirut.

Two attacks by Israeli warplanes hit fuel oil storage tanks at the coastal generating station, spilling up to 15,000 tonnes of fuel into the Mediterranean and fouling three quarters of Lebanon's 200-kilometre (124-mile) coast.

The air assaults came after Israel launched its blistering 34-day offensive on July 12 against Lebanese Shiite fighters from Hezbollah, and subsequent fires at Jiyeh burned for nearly two weeks.

The latest slick washed up on Syrian shores between the Lebanese frontier and Tartus, 260 km (161 miles) northwest of Damascus, Hassan Murjan, the head of environment services in Tartus, told AFP on Sunday.

"As long as the Lebanese coastline has not been cleaned there will be a risk for Syria," Murjan said. "We're waiting for the clean-up in Lebanon so we can get started again."

According to Rick Steiner, an American expert sent to the region by the World Conservation Union at the request of the Lebanese non-governmental group Greenline, "the longer pollution lasts, the more dangerous it becomes".

At a meeting last month in the Greek port of Pireaus, organised by the UN Environment Programme, a dozen countries promised logistical aid to battle the oil spill, considered the worst environmental catastrophe ever to befall Lebanon.

Greenpeace Mediterranean said that cleaning the massive spill could take up to a year.

The attack occurred ahead of a report this month by U.N. investigator Serge Brammertz on his inquiry in Hariri's killing. The Lebanese government plans in the next few weeks to authorize an international tribunal to try the culprits.

An initial U.N. report said Syrian security officials and their allies in Lebanese security agencies were involved in the bomb blast that killed Hariri in Beirut on February 14, 2005.

Damascus has denied any role in the assassination, which led to the withdrawal of Syrian troops from Lebanon in April 2005.

Hariri's death was followed by more than a dozen bombings that killed or wounded anti-Syrian politicians and journalists. The last such attack killed prominent Christian journalist and member of parliament Gebran Tueni on December 12.

Lt. Col. Samir Shehade was critically injured when a bomb went off near his car in the village of Rmaile near the southern port city of Sidon. It was not clear whether the bomb was placed under or near his car, said the officials, who spoke on condition of anonymity because they were not authorized to speak to the press.

Al-Arabiya TV station said Shehade had been involved in the arrest in August last year of four pro-Syrian Lebanese generals in Lebanon. The four were arrested on suspicion of involvement in the February 2005 assassination of former Lebanese prime minister Rafik Hariri.

The Tuesday explosion that wounded Shehade came just days before the United Nations chief investigator in the Hariri assassination, Serge Brammertz, was to hand his third report in the case to the United Nations.

Lebanon has been rocked by a series of politically motivated assassinations and bombings since Hariri's slaying, which some in Lebanon blame on Syria. Syria denies the allegations.

Israel has said it acted legally and accused Hezbollah of hiding among civilians in Lebanon and deliberately targeting Israeli civilians in rocket attacks. The fighting left 159 Israelis dead, including 39 civilians hit by Hezbollah rockets in Israel's northern cities. The Amnesty report also criticized Hezbollah's attacks on civilians.

The Foreign Ministry official said the legal-defense team, which includes representatives from the Justice and Defense ministries, is maintained by the government to help officials facing the possibility of war crimes charges abroad. It was first assembled to deal with charges related to Israeli actions in the West Bank and Gaza.

He would not comment on a report in the Haaretz daily that the ministry has urged top officials against making inflammatory statements that might be used against them in legal proceedings.

Israeli Tourism Minister Yitzhak Herzog said he isn't concerned about prosecution of Israeli leaders, but he criticized some officials for excessively belligerent statements during the war that could expose them to legal action abroad.

"Today we have to understand that wars, political situations and military situations include many components, and that one of the components that have to be weighed is international law," Herzog told Army Radio.

Israeli fears of prosecution abroad are based on experience. A retired general arriving in London last year who had commanded Israeli forces in Gaza was tipped off by an Israeli diplomat that he was about to be arrested by British authorities over a 2002 air strike that killed a Hamas leader and 14 others, nine of them children. Doron Almog remained on the plane and returned to Israel.

In 2001, then-Prime Minister Ariel Sharon faced a lawsuit in Belgium over his alleged role in a 1982 massacre in the Sabra and Shatila refugee camps in Beirut. Several former Israeli army chiefs of staff also have been targeted. None of the cases have succeeded.

Daniel Machover, a British attorney involved in attempts to prosecute Israeli officers including Almog, said he knew of "at least two" teams compiling evidence in Lebanon for use in future legal cases. He said it was "too early" to disclose more details.

The day after Abdallah's family arrived in Marwaheen, a small hilltop village a stone's throw from the Israeli border, Israel unleashed a barrage of artillery and airstrikes that reached Lebanon's glittering Mediterranean capital of Beirut and beyond.

The assault tore giant craters into roads across the country, making it too dangerous for Abdallah to leave Beirut. Hundreds, perhaps thousands, of charred cars still line the roads of war-wrecked towns, more than two weeks after a U.N. cease-fire ended the fighting, provoked by Hezbollah's July 12 capture of two Israeli soldiers.

Abdallah, 36, who holds jobs as a security guard and a coffee server at a communications company, called his wife in Marwaheen three times a day for the first three days of the war.

"She kept telling me 'Beirut is dangerous, it's being bombed, be careful,'" Abdallah said. "I told her 'I'll be fine, take care of yourself.'"

On the fourth day of fighting, he called at 7:30 a.m. "She told me 'We are fine,'" Abdallah said, and he felt reassured.

He called back an hour later. This time there was no answer.

Abdallah managed to reach a brother in nearby Sidon on the phone, who told him he'd heard the family had fled Marwaheen after Israeli forces ordered residents via loudspeakers to evacuate within two hours.

The panicked family had rushed to the local U.N. headquarters and begged U.N. peacekeepers to protect them. The peacekeepers turned them away, and the group decided the only way out was to risk Lebanon's deadly roads.

"There was a fire burning inside me. I couldn't think. I could only worry," Abdallah said of the uncertain hours that followed.

Glued to the television in his Beirut apartment, he saw a report about a convoy carrying civilians trying to flee Marwaheen that had been hit by an Israeli airstrike. More than a dozen were said to be dead.

A sick feeling came over him.

Desperate for news, he called his brother in Sidon. His brother told him he had something important to tell him, but he could not do it on the phone.

Abdallah knew what it was and wept.

Twenty-three people in the two-vehicle convoy were killed in the assault, carried out by an Israeli gunboat and an attack helicopter that strafed the survivors.

Only four people survived. One was Abdallah's 6-year-old daughter, Lara, who miraculously crawled out of the burning wreckage without a scratch, but covered in blood and screaming.

Her aunt, Zeinab, said Lara was in her mother's lap when the vehicle was struck and her mother's body had shielded her. Zeinab survived only because she had stepped away from the vehicle, which had overheated or broken down, and was sitting by the road.

His wife and five other children _ a 2-year-old daughter and sons aged 8, 12, 13 and 14 _ were killed.

"God protected her, this little girl," Abdallah said, cradling her in his lap. "I thank God. She is all I have left."

Across south Lebanon, the yellow flags of Hezbollah fly over the rubble of destroyed houses. Hung across roads in Hezbollah strongholds, yellow banners proclaim "Our Blood has Won" in Arabic, French and English. The Islamic militia says it won an asymmetrical war simply by surviving.

But there are no Hezbollah banners in Marwaheen. Here black flags fly from rooftops.

"Nobody won this war," Abdallah said, wearing black trousers and a black shirt.

He leaned down, put his cheek to Lara's and ran his hand through her hair. She hopped down and ran giddily from room to room, too young to understand she'll never see her mother and five brothers again.

On a wind-swept hilltop cemetery overlooking a deep valley, the 23 slain were buried Thursday in coffins under a patch of dark red earth. Simple cinder blocks topped with pictures kept in place by loose stones mark their locations until proper grave stones can be brought in.

"The Lebanese people, the civilians, we are the losers," Abdallah said softly. "We have lost everything."

Israeli officials quickly denied they had asked for a mediator, saying they requested Annan help secure the release of the soldiers, which is a condition of the UN-brokered ceasefire that ended the recent conflict, Reuters reported.

The July abduction of the soldiers sparked 34 days of Israeli airstrikes and Hezbollah rocket attacks.

The fighting ended with the ceasefire on Aug. 14, but the situation remains volatile and Israel has continued a crippling air and sea blockade of Lebanon, saying it remains necessary to prevent more weapons from reaching Hezbollah.

"The two sides have accepted the effort of the secretary general to help solve this problem," Annan told a news conference in Saudi Arabia. "I will appoint a person to work secretly with the two sides."

Earlier in the day, UN spokesman Ahmad Fawzi had said that both Israel and Hezbollah had requested mediation to resolve the dispute.

Hezbollah's chief spokesman, Hussein Rahal, refused to comment on the report.

Israel had demanded the unconditional release of the soldiers, but Hezbollah insisted it would only free them if Israel frees Arab prisoners.

The news of the mediator came as Annan continued an 11-day tour of the Middle East. On Monday, he met with Saudi Arabia's King Abdullah in the Red Sea port of Jiddah.

He had already met with officials in Lebanon, Israel, the Gaza Strip, Syria and Iran.