Farouq Qaddoumi, a founder of the Palestinian Liberation Organisation who later opposed the Oslo Accords, died in Amman on Thursday after a long illness, a friend said. He was in his 90s.
The head of the PLO's political department at the time, Mr Qaddoumi was sidelined when the group's chairman Yasser Arafat negotiated the landmark deal that established peace with Israel but did not result in Palestinian statehood.
Mr Qaddoumi, who was known by his nom de guerre, Abu Al Lutuf, then became a forlorn figure in Palestinian politics as other members of the old guard consolidated their position. Among them was President Mahmoud Abbas, who succeeded Mr Arafat in 2004.
"I mourn a brother and a friend and a companion in the struggle," Mr Abbas said in statement. "Palestine has lost one of its loyal men."
Unlike Mr Abbas and most other PLO leaders, Mr Qaddoumi refused to meet any Israeli official.
Born in 1931 into a land-owning family in the now occupied West Bank, Mr Qaddoumi studied politics at the American University in Cairo, where he met Mr Arafat and other Palestinian figures who founded the Fatah faction, precursor to the PLO.
He worked in professional jobs in Libya and Kuwait and eventually settled in exile in Beirut, before the 1982 invasion of Lebanon resulted in the expulsion of the PLO's leadership to Tunis.
Like most of the PLO's founders, Mr Qaddoumi was secular, having joined the Baath party in the 1940s. The Baath took power in Iraq and in Syria in the 1960s and Mr Qaddoumi often visited Damascus. He was careful not to be openly critical of Jordan, which signed a peace treaty with Israel in 1994. This enabled him to maintain a home in the kingdom.