The fate of Palestinian leader Yasser Arafat, close aides here say, hinges on the results of Syrian-backed political maneuvers in Damascus to have him replaced as chairman of the Palestine Liberation Organization.
They say the Syrians want the change to take place before the Arab summit meeting scheduled to take place in Saudi Arabia in November.
Mr. Arafat remains outside Tripoli in the area of two large Palestinian refugee camps, where his remaining loyalist military forces from the Fatah organization have been squeezed by the Syrians into their last bastion in Lebanon.
Senior Palestinian military officers here believe the Syrians and rebel Palestinian forces allied with them will hold off from a direct assault on loyalist Fatah forces until the political maneuvers run their course.
''If they fail by diplomacy, the Syrians will move,'' says Col. Ziad Atrash, commander of Fatah militias and of the Yarmuk Brigade. He was forced by the Syrians two weeks ago to leave Lebanon's Bekaa Valley with 1,100 loyalist Fatah troops.
But as Palestinian troops dig in, heavy fighting in the city between Arafat-backed Muslim fundamentalists and Lebanese leftists loosely allied to the Syrians hints at a showdown ahead.
Arafat has been under heavy pressure since a May rebellion in his Fatah organization. The rebellion has been increasingly supported - and, he charges, taken over - by the Syrians. The expulsion of Colonel Atrash's men from the Bekaa has left Arafat's remaining several thousand fighters surrounded near Tripoli by an estimated 9,000 Syrians. The Syrians hold the high ground. Behind the Palestinians are only the city of Tripoli and the sea.
Arafat believes Syria wants to control the PLO as a key bargaining chip in political negotiations. He is convinced that the United States supports this.
Earlier this week the last offices in Damascus loyal to Arafat were taken over by Fatah rebels in armed attacks that left two loyalists dead. While the Syrian authorities claimed the matter was an internal Palestinian affair, Arafat aides here point out that an armed attack in central Damascus could not happen without official Syrian government endorsement.
Sporadic skirmishes between groups of rebels and loyalists have been occurring in the two refugee camps here, the latest at Nahr al-Bared camp on Monday.
Palestinian leaders based in Damascus, including rebels and fence-sitters, have been meeting this week to discuss the split. Salah Khalaf (Abu Iyad), a senior Fatah official and loyalist, charged in an interview in Kuwait that the rebels and Syrians were intent on replacing Arafat with Khalid Fahoum, the Damascus-based chairman of the Palestine National Council (PNC), the Palestinian parliament in exile.
The Fatah rebels have been calling for a meeting of Fatah leaders to replace Arafat with a leadership committee. But this has been impossible both logistically and because of the bitter division between the loyalists and rebels. Arafat has not even been permitted to enter Syria since he was kicked out of Damascus on June 24. He has bitterly labeled the rebels ''puppets.''
Thus, if they wish to replace Arafat, the rebels and the Syrians must find some way to legitimize the move so as not to lose the official Arab endorsement of the PLO as the ''sole spokesman'' of the Palestinians.
Key to such legitimacy appears to be endorsement by leading PLO figures from other organizations than Fatah, and also by independents. Arafat aides believe the Syrians will try hardest to win support for the change from George Habbash and Naif Hawatmeh, leaders of Marxist PLO factions which differ politically from Arafat but so far have stood firmly for unity in the organization.
Arafat aides say the Syrians would like to convene a special session of the Palestine National Council in Damascus to endorse a replacement for Arafat.
''What happened to our offices in Damascus is a message to Habbash and Hawatmeh,'' said Ahmed Abdul Rahman, spokesman for Arafat, noting that both are based in Damascus. ''But,'' he added, ''they won't go along.''
Arafat is trying to fight back through political maneuvers but is acting from a weak position.
Despite much publicity about a rapprochement with King Hussein as a possible prelude toward renewed talks on forming a joint Jordanian-Palestinian negotiating team, such a possibility seems remote.
Mr. Abdul Rahman says Arafat was misunderstood by journalists who recently reported he would visit Amman. What he actually said, according to his spokesman , is that he was ''ready to'' visit Amman. But no invitation has yet been tendered.
Talks between Jordan's King Hussein and Arafat broke down in April when the PLO leader could not provide a PLO green light for a joint Jordanian-Palestinian negotiation delegation which would sit down with Israel on the basis of the Reagan Middle East peace initiative. At the time the King said he would resume a dialogue only if Arafat based it on points the two leaders had worked out in negotiations, including acceptance of the Reagan plan.
But Abdul Rahman specified that Arafat was willing to resume the dialogue only on the basis of the Arab states' Fez plan, which is less specific about accepting the state of Israel and was previously rejected by King Hussein as the sole basis of a joint platform.
Thus, it does not appear that Arafat is yet ready to make the kind of concessions that might attract the King.
Arafat appears to be relying heavily on mediation efforts by the Algerians and the Saudis. He also appears to be counting on his contacts with President Assad's brother Rifaat, Syrian special forces chief. These forces, linked with a branch of Syrian intelligence, have a substantial presence in the Tripoli area.