The UN has urged European countries to come forward to contribute more troops for the peacekeeping force in Lebanon.
Lebanese troops have reached the southern border with Israel
Deputy Secretary General Mark Malloch Brown thanked Asian nations for their firm commitment but added the force had to be "multilateral" in character.
The call came after Israel said it might be "inconceivable" to accept nations that denied its right to exist, such as Malaysia and Indonesia.
A 15,000-strong UN force is planned to police the truce in southern Lebanon.
Under the terms of the UN ceasefire resolution which ended the month-long conflict between Israel and Hezbollah, the expanded UN force should work alongside about 15,000 Lebanese troops to keep the peace.
France has agreed to lead the force if its mandate concerns are but its immediate pledge of only 200 extra troops is far smaller than expected.
"There's been different signals coming out of France," US President George W Bush said.
"We hope they send more."
Two senior UN envoys, Vijay Nambiar and Terje Roed-Larsen, have arrived in Beirut for talks on how the UN-brokered truce is being implemented.
Heavy Israeli air activity over Hezbollah's Bekaa Valley heartland early on Saturday has been reported by Lebanese sources.
It was not immediately clear if any air strikes had been made.
Mr Malloch Brown said the commitment of troops by Indonesia, Malaysia, Bangladesh and Nepal among others was "enormously helpful and a major contribution".
UN TROOP PLEDGES
France - leadership and 200 troops
Bangladesh - two battalions (up to 2,000 troops)
Malaysia - one battalion (up to 1,000 troops)
Indonesia - one battalion, an engineering company
Nepal - one battalion
Denmark - at least two ships
Germany - maritime and border patrols
Sources: UN diplomats
But he said the force should have a "multilateral character so that it enjoys the confidence of both sides".
French Defence Minister Michele Alliot-Marie warned that soldiers could not be told: "Look what's going on but you don't have the right to defend yourself or to shoot".
Mr Malloch Brown said the new force would not be "offensive", nor would it be asked to "attempt large-scale disarmament".
"Rather it is going to police the political agreement which triggers disarmament called for under the resolution," he said.
Use of force would only be exercised if combatants forcefully resisted a demand to disarm, Mr Malloch Brown said.
A 3,500-strong vanguard is planned to be in place in the next 10 days.
European powers have so far been reluctant to sign up but Italy on Friday confirmed it was approving sending troops to Lebanon.
Germany has offered a maritime task force. The UK and the US say they will provide logistical support.
Israeli UN envoy Dan Gillerman said earlier it would be "difficult if not inconceivable" to accept nations that did not recognise Israel's right to exist.
Mr Gillerman said Israel would be "very happy" to accept troops from Muslim countries they have friendly relations with.
Israel says it has now withdrawn from two-thirds of its positions in southern Lebanon, including the port city of Tyre and villages of Qana, Hadatha and Beit Yahoun.
Lebanese troops have reached the southern border with Israel - a vehicle carrying a Lebanese flag made a symbolic pass a few metres from the border at Kfar Kila.
The UN says 400,000 people have returned to homes in the south and in the heavily bombed southern suburbs of Beirut.
Lebanese President Emile Lahoud has praised what he called the victory of Hezbollah against Israel in a televised address to the nation.
He said he saluted Hezbollah leader Sheikh Hassan Nasrallah "who willed this victory to be a victory for all Lebanese and all the Arab peoples".
At his presidential retreat in Camp David, Mr Bush again condemned Hezbollah as a "force of instability".
"Sometimes it takes people awhile to come to the sober realisation of what forces create stability and what don't," he said.