The first shipment of American aid for Lebanon arrived in Beirut on Tuesday and Israel promised to open vital safe passages as humanitarian groups pushed more convoys of supplies to tens of thousands in the war-torn south. The United Nations has been pressing Israel to set corridors into the south, where Israeli bombardment has devastated the road network and struck vehicles - including trucks, believing they are carrying weapons to Hizbullah. Prime Minister Ehud Olmert told visiting Secretary of State Condoleezza Rice in Jerusalem that Israeli military officials will meet with international military experts to outline the pathways, according to his office. UN humanitarian chief Jan Egeland, also visiting the region, said earlier in the day that he believed a humanitarian aid convoy could move from Beirut to southern Lebanon on Wednesday if the Israeli army gave final approval. Egeland said he had received a "positive response" from Israeli army officials. "We hope to have the first convoy going down from Beirut already Wednesday morning and another one on Friday," Egeland told Israel Army Radio. Military helicopters brought the US shipment into Beirut, the first since President Bush ordered a Navy task force that had been evacuating Americans from Lebanon to shift gears and start bringing in aid. The shipment included two large-scale medical packages "aimed at meeting the most urgent needs," holding enough medicine and health supplies for 20,000 people for three months, the US Embassy said. The goods were given to the international Red Cross to distribute, it said. Washington has launched the aid effort in an effort to show it supports Lebanon at a time when many here are furious at it for refusing to press Israel to halt the bombardment that has killed hundreds, driven up to 750,000 people from their homes and demolished infrastructure. Israel launched the assault to rein in Hezbollah after it captured two of its soldiers July 12. US Ambassador Jeffrey Feltman said the shipment was the first in $30 million worth of aid from the United States. "We hope it will address some of the most pressing needs of the conflict victims. The United States remained deeply concerned about the humanitarian situation in Lebanon." Asked if there were a contradiction between US arms sales to Israel and aid supplies to Lebanon, Feltman said Washington's position was based on "two pillars to how we need to deal with the conflict. One pillar is humanitarian assistance. ... The other is to find conditions for a sustainable cease-fire." Also Tuesday, a Greek warship brought in 80 tons of tents, blankets, cooking sets and hygiene sets, which include soap, toothpaste and other items, gathered by the French humanitarian group Medecins Sans Frontieres. Israel has loosened its 13-day blockade of Lebanon's ports to allow aid ships into Beirut, but it has not responded to UN requests that it also open the southern port of Tyre, located inside the war zone. Opening Tyre, 40 miles south of Beirut, would allow massive injections of material directly to tens of thousands who are in need without having to move aid by truck along the dangerous and winding roads from Beirut. So far, Israel has defined one land route, leading north from Beirut to Tripoli. To get to the south, Israel will define routes on a convoy-by-convoy basis instead of setting a single, permanent corridor, said Mona Hammam, the top UN humanitarian coordinator in Lebanon. The UN is also waiting for word from Israel on a corridor from Syria into Lebanon before it can start moving mattresses, blankets, tents, gasoline cans and stoves it has stockpiled in Syria, said Jennifer Pagonis, a spokeswoman for the UN High Commissioner for Refugees in Geneva. "We have no word of a safe corridor in Lebanon," she told The Associated Press. "Our trucks are still in Damascus waiting to go." She said the UN agency wanted a direct guarantee from Israel that its supply convoys would be able to pass through the Syria-Lebanon border zone safely. Otherwise, Pagonis said, "it's not very practical for our immediate needs." The goods are meant for some 20,000 refugees from the south who have taken shelter in the northern and central mountains. The international Red Cross has sent three convoys to the embattled southern port city of Tyre in the main war zone - the latest heading out on Tuesday - and another to the southern city of Marjayoun, according to ICRC spokesman Hisham Hassan. At the same time, Red Cross experts on health care, shelter and nutrition were conducting surveys in villages and towns around Tyre and Marjayoun, 24 miles to the east, to determine the needs of people still in the zone of heaviest fighting. The UN convoy on Wednesday was to head to Tyre carrying drugs for hospitals in the region, high-energy bars and 90 tons of flour, enough for 10,000 people for a month, said Mona Hammam, the top UN humanitarian coordinator. Egeland has issued an urgent appeal for $150 million in aid to Lebanon, where tens of thousands of refugees are in temporary shelters, supplies of medicine are tight at many hospitals, and fuel is slowly running out. King Abdullah of Saudi Arabia has decreed donations totaling $1.5 billion to Lebanon, assigning $500 million for its reconstruction and $1 billion to be deposited in Lebanon's central bank to support the economy. He also ordered a grant of $250 million to the Palestinians, the statement said.