U.N. Secretary-General Kofi Annan called on Israel on Tuesday to end its air and sea blockade of Lebanon and appealed for the quick release of two Israeli soldiers captured by Hezbollah guerrillas.

Annan arrived in Israel on Tuesday afternoon after visiting U.N. peacekeepers in southern Lebanon who are to play a key role in maintaining the fragile truce that ended 34 days of fighting between Israel and Hezbollah guerrillas.

He met in Jerusalem with the families of two soldiers whose capture by Hezbollah on July 12 sparked the fighting as well as with Defense Minister Amir Peretz.

Annan said he spoke with Peretz about lifting the blockade "as soon as possible in order to allow Lebanon to go on with normal commercial activities and also rebuild its economy." Annan earlier called the blockade a "humiliation and an infringement on (Lebanon's) sovereignty."

"I hope we can find a way to lift it," Peretz said without elaborating.

Israel has said it will only lift the blockade once it is assured that forces deployed on Lebanon's borders can prevent Hezbollah from importing new weapons to rearm itself for another round of fighting. Israel wants international forces to help patrol the Lebanon-Syria border to stop the arms flow. Lebanon has said that its troops would be able to secure the border on their own.

"Israel will be happy to stop the sea and aerial blockade if we felt that the land crossings would not be the main smuggling routes," said Israeli government spokeswoman Miri Eisen. "Israel is certain that if there is no serious force to stop (smuggling), both Syria and Iran will continue to back, fund and arm Hezbollah in Lebanon."

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Annan said Israel was responsible for most of the violations of the cease-fire and appealed for everyone to work together to ensure the peace holds and "not risk another explosion in six years or 20 years."

Israel says its troops will remain in southern Lebanon until a sufficiently strong contingent of Lebanese troops and international forces arrives to take control of the area. Annan said the U.N. hoped to have 5,000 soldiers in the region by Friday. That is double its pre-war number, but still far short of the 15,000 international troops who are eventually supposed to patrol the border.

"Israel will pull out once their is a reasonable level of forces there," Peretz said.

Israeli Prime Minister Ehud Olmert, who is to meet with Annan on Wednesday morning, would also call for "the unconditional return of our captives in Lebanon," Eisen said.

The families of the two captured soldiers, Ehud Goldwasser and Eldad Regev, said after their meeting with Annan that he had no new information about the men, who have not been heard from since their capture.

"But the good news was that we got a personal pledge from the secretary general of the UN that he accepts the mission to get the three kidnapped soldiers home and that's a really big thing," Goldwasser's wife, Karnit, told Israel TV.

"(Hezbollah) must first of all give us a sign of life. (Annan) must act toward that. It's a moral demand that's basic in any negotiations," said Regev's brother, Benny.

Before traveling to Israel, Annan visited U.N. peacekeepers in Naqoura, about 2.5 miles north of the Israeli border, and the base for the U.N. Interim Force in Lebanon, known as UNIFIL.

Annan was briefed by French Maj. Gen. Alain Pellegrini, the UNIFIL commander, and other top officials, then reviewed an honor guard of U.N. troops in blue berets standing at attention on the green lawn inside the U.N.'s white-walled compound.

He laid a wreath at a monument for nearly 300 peacekeepers killed in Lebanon since UNIFIL deployed here in 1978. Muslim and Christian clergymen said prayers, and the U.N. chief stood in silence in front of a display of portraits of those killed, including four UNIFIL members killed in a July 25 Israeli airstrike on their base in Khiam.

Annan left Naqoura after about 2 1/2 hours and flew along the border by helicopter, surveying UNIFIL posts by air before heading south to Israel.

The U.N. chief shook hands with members of the 2,000-member force, which is being expanded to 15,000 under the U.N. resolution that halted fighting between Israel and Hezbollah on Aug. 14. Flags of countries contributing troops to UNIFIL, including Annan's native Ghana, fluttered in the breeze as a military band played their national anthems.

Annan told the troops their role was something that has been "misunderstood and criticized" and that they were "never given credit for the wonderful things they have done and the sacrifices they have made."

He said much could be done to speed up the handover of south Lebanon from Israeli troops to multinational ones. "With good will it can be done faster than we are doing. On our side, we are trying to get in the additional reinforcements as quickly as we can," he said.

After talks with Lebanese leaders in Beirut on Monday, the U.N. chief faulted both Israel and Hezbollah for not living up to key sections of the cease-fire resolution.

"Without the full implementation of resolution 1701, I fear the risk is great for renewal of hostilities," he said.

He also toured a bombed-out neighborhood in the Hezbollah stronghold of south Beirut, where hundreds of residents booed him.

Annan said Tuesday he found the destruction "quite shocking," and said he could "understand the anger and frustration of some of those who had lived there."

"But what happened yesterday was really a little side show put on to impress me, and I think some of the young ones got a bit overzealous," he said in reference to the booing.

Meanwhile, an Italian task force gathered off the coast of southern Italy on Tuesday to carry troops and aircraft to south Lebanon. A thousand Marines and engineer corps specialists were leaving as the first of a 2,500-strong Italian contingent.

Annan's Mideast tour was also to take him to Syria and Iran — Hezbollah's main benefactors, shunned by the United States during the monthlong Israel-Hezbollah war.