But Israeli and Hezbollah forces held their ground and raised hopes that the U.N.-imposed pact could stick.
Hezbollah guerrillas fired at least 10 rockets in southern Lebanon, but none crossed the border into Israel. On Monday, at least six Hezbollah militiamen were killed by Israeli troops waiting for a peacekeeping force before beginning a full-scale withdrawal.
Lebanon was under intense international pressure to get soldiers moving south into Hezbollah territory - a key element in the U.N. Security Council plan to end the 34-day conflict that claimed more than 950 lives, according to the AP.
Lebanon's defense minister, Elias Murr, said Lebanon's contribution of 15,000 soldiers could be on the north side of the Litani River by the end of the week. But they still must cross the river and try to enforce the central government's control over Hezbollah areas for the first time in decades.
In Jerusalem, Israeli army officials said they plan to begin handing over some captured positions on Wednesday and hope to complete the withdrawal from Lebanon by next week, the AP reports.