U.N. Secretary-General Kofi Annan is due to meet Wednesday with Israeli Prime Minister Ehud Olmert as part of a Mideast tour intended to shore up the U.N. brokered ceasefire in Lebanon.

Mr. Olmert's spokeswoman says he plans to call for the unconditional return of two Israeli soldiers captured by Hezbollah last month. Their capture triggered a month-long war between Israel and the guerrilla group.

On Tuesday, Mr. Annan held talks with Israeli Defense Minister Amir Peretz. The U.N. chief later said Israel is responsible for most of the violations of the Israel-Hezbollah ceasefire in Lebanon.

Peretz said Israel will pull its forces out of Lebanon when what he called a "reasonable" number of international troops are deployed along Lebanon's borders. Mr. Annan said the U.N. hoped to double its 2,500-strong force in southern Lebanon by Friday.

In an earlier stop Tuesday in southern Lebanon, Secretary-General Annan urged Israel to lift its air, land and sea blockade of Lebanon. Israeli officials say they will not lift the blockade until U.N. peacekeepers on Lebanon's borders can stop arms shipments to Hezbollah.

Also Tuesday, Mr. Annan met with the families of the two captured Israeli soldiers. The families asked the U.N. chief to press for the soldiers' release.

Mr. Annan's Middle East tour is aimed at shoring up the ceasefire that ended the fighting between Israel and Hezbollah. He will also visit Syria and Iran - the top supporters of Hezbollah.

Some information for this report was provided by AFP, AP and Reuters.