The March 14 camp also accused Syria of involvement in Tuesday’s bus bombings in a predominately Christian area northeast of Beirut that killed three people and wounded 20.
In a series of speeches, government and coalition politicians called for the implementation of UN tribunal to investigate the killing and other political assasinations, including that of Pierre Gemayel, a government minister, last November.
Saad Hariri, the son of Rafiq al-Hariri, said that "[only] the international court will enable us to stop these serial assasinations that have been targeting our country, our elite and our politicians for the last 30 years".
Despite reports over the last few days that the government and the opposition coalition were moving closer in their position, several leaders took the opportunity to declare that they would not compromise their postion.
"All Lebanese we shall remain loyal to our governments promise to have a sovereign free secure and safe Lebanon, a strong government, a capable government to fulfil the ambitions of the citizens," Samir Geaga, leader of Lebanese Forces, a Christian party, told the crowd.
Geagea also said that the only weapons in Lebanon should be in the hands of the Lebanese army, a direct reference to the weapons possessed by Hezbollah forces.
The most outspoken comments came, however, from Walid Jumblatt, the leader of the Druze faction in parliament.
In a direct attack on Bashar al-Assad, the Syrian president, Jumblatt said: "You are like a monkey, a snake, a whale, you are like a monster, you are not even up to being described as a human."
Troops backed by tanks were deployed in considerable numbers across Beirut during the rally as government supporters travelled from around the country to al-Hariri's grave on Martyrs' Square.
Security was tight amid fears of possible confrontation as the demonstrators massed in the square where opposition activists have been holding an around-the-clock sit-in since late last year.
Fears that Tuesday's bombings may deter many people from attending the rally did not materialise.
|Al-Hariri supporters crammed into the |
Martyrs' Square wherever they could [AFP]
Mike Hanna, Al Jazeera's correspondent in Beirut, said current events meant people were more determined to show their respects for al-Hariri, whom they saw as a unifying figure in Lebanese politics.
Indeed, fears of friction between supporters of the rival political groups also proved unfounded.
Hanna said there was a largely friendly atmosphere in the rally, such was the respect commanded by the assassinated prime minister in Lebanon.
Opposition politicians were adamant the rally should proceed undisturbed.
Hassan Nasrallah, the Hezbollah leader, apologised for his decision not to attend the commemoration.
In an article in As-Safir newspaper, he said, addressing the late al-Hariri, "our only sin is that we refused to accuse without evidence or to turn your blood into a weapon for vengeance".
Roads leading to Beirut on Wednesday were clogged by convoys of vehicles loaded with people, who then walked the last 5km to reach Martyr's Square on foot.
"I came here as a commitment to February 14 and to put flowers on the grave of Hariri, who taught and built," 33-year-old Amid al-Baayni, said.
"We came in defiance of those planting bombs," another al-Hariri supporter, Omar Qabbani, said.
"Lebanon had suffered enough and nobody wants the Iraqi scenario to be repated in Lebanon "
Nehad Ismail, London, UK
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"We want to live. All Lebanese people should rise up to stop this cycle of terrorism," said Nadia Saikali, a housewife from the Christian neighbourhood of Ashrafiyeh in Beirut.
A clock in the square counts in luminous red numbers the days since his death: 730.
Some demonstrators took turns to pray in front of the grave.
Others climbed the square's statue, which commemorates Lebanese martyrs of the Ottoman era.
At exactly 12:55pm, the time of the deadly explosion, the crowd fell silent except for a muezzin making the Islamic call to prayer and the tolling of a church bell. Standing at the speaker's podium, Saad al-Hariri and his aunt, Bahiya, prayed.
The cabinet has declared Wednesday a day of national mourning, with government and educational institutions and businesses shut.
The UN Security Council and the Lebanese government have approved plans for a tribunal to investigate al-Hariri's death, but Lebanon's pro-Syrian president has not ratified the deal, and Nabih Berri, the parliament speaker and leader of the opposition Amal party, has refused to call the chamber to vote on the plan.