As the International Court of Justice in The Hague began discussing the legality of the barrier on Monday, thousands of Palestinians in the West Bank and Gaza Strip marched in protest against the wall.
More than 10,000 Palestinian demonstrators, including many government employees and students, marched in most West Bank towns.
In two locations, near the towns of Jenin and Tulkarem, soldiers fired tear gas to keep thousands of marchers from coming too close to the barrier.
In Bethlehem and the Jerusalem suburb of Abu Dis, troops fired tear gas to disperse stone throwers, and three people were treated for tear gas inhalation.
"Huge numbers of Israeli soldiers took up rooftop positions on the high buildings surrounding the protest site, in an attempt to identify the protesters' position and disperse them," said Aljazeera correspondent Shireen Abu Aqla, reporting from Abu Dis.
"The soldiers fired tear gas and live bullets to disperse the stone-throwing protesters as they got close to them," said the correspondent.
Ambulances were seen transferring injured Palestinians to hospitals, added the correspondent.
Marches also took place in Qalqiliya, a town ringed by a tall wall as part of the separation project, as well as in Nablus and Ram Allah. "The wall must fall," read a banner carried by Ram Allah marchers.
Meanwhile, pro-Israeli sympathisers organised a silent protest march near the UN International Court of Justice in The Hague.
Israel sympathisers have called
for "end to terrorism"
Participants, who were marching towards the court building, were carrying photos of casualties from Palestinian attacks carried out in Israel, as well as banners and Israeli flags.
The burned-out shell of an Israeli bus that was shattered by a human bomb attack had been placed near the court building, along with banners calling for "an end to terrorism".
Demonstrations also spread to the Palestinian refugee camp of Ain Heloue in southern Lebanon, where about 4000 people, predominantly school pupils, brandished portraits of Arafat and shouted slogans against "the wall of racist segregation."
About 500 representatives of non-government organisations, including the Middle East Council of Churches, handed in a petition at the headquarters of the United Nations in Beirut calling for the barrier to be demolished.
Hundreds of Palestinians staged a protest sit in at the offices in Tripoli, northern Lebanon, of the UN Relief and Works Agency, which was set up to aid the refugees.
Children demonstrate in Beirut in
front of the UN headquarters
In Cairo, about 7000 students demonstrated both against the
wall and French plans to ban Muslim veils in schools. Under the eyes of a heavy force of police, they brandished a banner reading, "the veil or the wall: which of these two is a symbol of terrorism?"
Dozens of demonstrators sat down before the headquarters of the European Union in Damascus, demanding international action against what they described as Israel's "racist crime."
Israel says the barrier, consisting of fences, trenches and walls, is its last line of "defence against Palestinian suicide bombers", who have killed 463 people, most of them Israelis, since the outbreak of the current round of fighting in 2000.
The Palestinians say the barrier, which is to run up to 740 kms and at times dips deep into the West Bank, amounts to a land grab.
The partition, about one-third completed, disrupts the lives of tens of thousands of Palestinians who have difficulties getting to fields, jobs and schools.