Officials from nations that have offered to send troops to Lebanon will meet at the United Nations Thursday to determine the size and make up of the international force that is to assist the Lebanese army in southern Lebanon. Diplomats continue to clarify issues about the deployment and role of the international force.

U.N. officials say they hope 3,500 troops will arrive in southern Lebanon within 10 days to reinforce the 2,000 member U.N. force already in place.   The resolution ending the fighting between Israel and Hezbollah forces in the south of Lebanon authorizes a force that could eventually include as many as 15,000 U.N. and international troops to help the 15,000 Lebanese soldiers being sent to the south.

U.S. ambassador John Bolton says adequate security in the form of an enhanced U.N. force must be in place before the Israeli withdrawal begins in order to prevent Hezbollah forces from re-infiltrating the area.

"The mechanism that the resolution sets up is that all of this parallel activity of the deployment of the international force, the deployment of Lebanese armed forces and the withdrawal of the Israeli forces is to take place in parallel and in a coordinated fashion," he said.  "I think the commanders on the ground have to make a judgment whether the situation at some point is ripe for this parallel action to begin and whether that is sufficient to preclude the vacuum from being created. That is the real question. It is: Will the Israeli withdrawal create a vacuum that allows Hezbollah to re-enter, which is what we want to avoid."

Bolton says the Security Council's objective is to enforce resolutions clearly stating that there can only be one legitimate government in Lebanon and that armed militias must be disarmed.

Israeli Foreign Minster Tzipi Livni met with Secretary-General Kofi Annan to discuss implementation of the resolution. She said an arms embargo is crucial to its success and the future of the region.

"This is not only an Israeli interest, this is a Lebanese interest," she said.  "Nobody can speak in terms of disarming Hezbollah when meanwhile we can see a process of rearmament of Hezbollah. There is a need that this embargo will be effective.  We think that the Lebanese government monitoring the borders is not enough.  We expect that the new international force will assist the Lebanese government to monitor the international borders in order to prevent Iran and Syria from rearmament of Hezbollah."

Questions about the size and make-up of the international force should clarify during the Thursday meeting of troop-contributing nations. Meanwhile, Secretary General Annan is sending a high level mission to Israel and Lebanon Thursday to secure the full implementation of the resolution. Special envoys Vijay Nambiar and Terje Roed-Larsen will lead the mission.