Rival Palestinian movements began a two-day "national dialogue" in an attempt to bridge differences that have pushed the Hamas-led government and its opponents into open conflict.
President Mahmoud Abbas said today he would call a referendum on a Palestinian proposal seeking a negotiated settlement with Israel if rival factions could not agree on the plan.
Mr Abbas said he would give delegates to a current 'national dialogue' meeting between Islamic group Hamas and his own Fatah movement up to ten days to reach an agreement on the plan before calling for a popular vote.
"If you do not reach agreement by then, I would like to tell you frankly that I will put this document to a referendum," Mr Abbas told the delegates. "This is not a threat."
The plan, drawn up by members of both Fatah and Hamas who are in jail in Israel, calls for resistance but a negotiated settlement with Israel if the Jewish state withdraws fully from West Bank land it has occupied since 1967. It also calls for a unity government and for Jerusalem to be the capital of a Palestinian state in the West Bank and Gaza.
Many Palestinian factions support the plan, but senior Hamas leaders have not yet signed up to it. Hamas, whose charter calls for Israel's destruction, does not recognise Israel's right to exist, which is implicit in the proposal being put forward.
In recent weeks, Mr Abbas has repeatedly offered himself as a partner to resume long-stalled peace talks with Israel, in contrast to Hamas, whose charter officially calls for Israel's destruction and which describes peace talks as pointless.
Both Israel and Fatah have called on Hamas to renounce violence, recognise Israel's right to exist and abide by existing peace agreements, demands rejected by Hamas.
Israeli Prime Minister Ehud Olmert has said he will try to pursue talks with Mr Abbas, but he has said he cannot deal with the Palestinian Authority with Hamas in power, a position reiterated in his address to the US Congress yesterday.