The Palestinians will ask the U.N. Security Council to set up an international commission to investigate the death of Palestinian leader Yasser Arafat, a senior Palestinian official said. Farouk Kaddoumi, head of the Palestine Liberation Organization's mainstream Fatah faction, made the announcement Saturday after meeting in Damascus with representatives of the Syria-based Palestinian factions. The meeting discussed the Palestinian-Israeli conflict and Arab developments. The PLO will submit a request to the U.N. Security Council "to form an international investigating commission into the assassination of Palestinian leader Yasser Arafat," Kaddoumi told reporters. Arafat died in a French hospital Nov. 11, 2004. The cause of death remains unknown, according to a report of The Associated Press. Kaddoumi said Arafat was poisoned by Israel "because he was a stumbling block to (Israeli) plans." He added that all Palestinian groups are united in holding Israel fully responsible for Arafat's death. Khaled Mashaal, the political leader of the Palestinian "Hamas" group, who attended Saturday's meeting, had previously accused Israel of killing Arafat by poisoning him. On Friday, the Palestinians in the West Bank marked the first anniversary of Arafat's death. Arafat died in a military hospital outside Paris, two weeks after being flown there from his bullet-scarred Ramallah base in the West Bank, where he had been cooped up for three years under Israeli siege. The Percy Military Hospital that treated him has not clarified the cause of death, and its medical records on Arafat, recently leaked to reporters, have proven inconclusive. Arafat's nephew, Palestinian Foreign Minister Nasser al-Kidwa, said Friday he's convinced his uncle didn't die of natural causes, and that Israel killed him. On Friday, about 2,000 Palestinians in the Yarmouk refugee camp in Damascus commemorated the first anniversary of Arafat's death. Addressing the crowd, Mashaal reiterated that Israel had poisoned Arafat and pledged to avenge his death.