"America out!" yelled supporters of the Shia Islamist group at a rally in the southern town of Nabatia on Sunday, mocking chants of "Syria out" that have resonated in central Beirut streets in recent weeks.
It was the second time in a week the Hizb Allah resistance group, which has the largest following in the country and is the only one with weapons, had flexed its muscles.
Hundreds of thousands of people gathered in central Beirut on Tuesday to support Hizb Allah's right to bear arms and to thank Syria for its role in Lebanon, where Damascus has kept troops since a 1976 civil war intervention.
Many placards read "No to foreign intervention". The crowd, waving Lebanese flags, chanted "Death to America, death to Israel" at the rally organised by Hizb Allah and the smaller Shia Amal party.
Commenting on the Nabatia demonstration, Muhammad Qabani, a Lebanese opposition MP, told Aljazeera on Sunday: "The opposition has always said it is not alone in the street and does not say it represents all Lebanon.
"But the opposition represents the Lebanese majority and that will be seen clearly on Monday from the opposition's planned sit-in. It is not a matter of numbers but of the manner in which a demonstration takes place."
Meanwhile, UN envoy Terje Roed-Larsen has held meetings with President Emile Lahud and other officials to discuss implementing United Nations resolution 1559, which calls for a complete withdrawal of foreign forces from Lebanon and the disarming of all militias.
Roed-Larsen said his talks on Sunday with Lahud in Beirut on the UN resolution were "constructive" and they had agreed that elections, expected in May, must go ahead on time.
Political tensions over Syria's role in Lebanon had stirred talk of a postponement.
"We agreed together that the coming parliamentary elections must occur on time and in a free and fair way," he said.
UN envoy Terje Roed-Larsen is
seeking a full Syrian pullout
Roed-Larsen last visited Lebanon and Syria days before the 14 February killing of former prime minister Rafiq al-Hariri, which sparked daily protests in Beirut against the Syrians and redoubled global pressure for the Syrians to leave.
Roed-Larsen said on Saturday Syrian President Bashar al-Asad had promised to withdraw all his troops and intelligence agents from Lebanon in line with the resolution.
He said he would present UN Secretary-General Kofi Annan with more details of a timetable for a complete Syrian pullout from Lebanon when he arrives in New York early next week.
Al-Asad said last week Syria would withdraw its troops from Lebanon in two phases, first pulling back to eastern Lebanon, then agreeing with the Lebanese on how long any should stay.
In his interview to Aljazeera, Lebanese opposition MP Qabani hailed Roed-Larsen's statement on Syrian's planned withdrawal as "a good step".
But asked whether this will create a suitable atmosphere for opposition participation in a national unity government or the holding of elections in Lebanon, he said: "We have demands - namely, an international investigation committee into the assassination of Rafiq al-Hariri and the resignation of the chiefs of the security apparatuses. There can be no fair election while they are around."
Qabani added: "We are not acquainted with the [Syrian military pullout] time-table. Our demand is that the withdrawal should be in line with the Taif Accord."
Incidentally, under the accord, Hizb Allah, as the main armed group fighting Israeli occupation of Lebanon's south, was allowed to keep its arms when other militias were disarmed. It drove Israel out after a 22-year occupation in 2000.
In Nabatia on Sunday, protesters, who were mostly Shias but were joined by some Druze and others, came from across southern Lebanon to support Hizb Allah's armed "Islamic resistance", witnesses said.
Hizb Allah's Nasr Allah has put
Lebanon's opposition on notice
Some burned Israeli and US flags. "Resolution 1559 was made in Israel" a placard read.
Some protesters held their Lebanese identity cards up so that no one could say they were bused in from Syria, as some media reported after last week's Hizb Allah rally in Beirut.
Reacting to the sectarian divisions underscored by the Shia-supported Hizb Allah and Amal rallies, Lebanese opposition MP Qabani told Aljazeera: "We do not want sectarianism but an accord among all Lebanese. There are independent Shia elements within the opposition.
"We have always said we need to hold a dialogue with Hizb Allah, which has a wide and genuine representation. We seek to build one nation, jointly."
For their part, Syrian troops continued to withdraw on Sunday, leaving posts in Mount Lebanon, northeast of Beirut, as Lebanese soldiers stood by to take over. All Syrian troops have now left northern Lebanon, ending an unbroken 29-year presence.
The United States and France, divided over Iraq, joined forces in September to push through Resolution 1559, which demands foreign troops leave Lebanon but does not specify when.
US Secretary of State Condoleezza Rice said on Friday the withdrawal so far fell short of US demands for a full pullout.
"It's not a bad thing that Syrian forces are moving - clearly not a bad thing - but it is also not compliance with 1559," she told journalists.