PARIS - France warned on Friday it would recognise a Palestinian state if a final international effort to overcome the impasse between Israelis and Palestinians failed, and proposed a two-year timeframe to end the conflict through a UN-backed resolution.

Lawmakers will hold a symbolic parliamentary vote on Dec 2 on whether the French government should recognise Palestine as a state, a move that the Israeli Prime Minister has called a "grave mistake". "If this final effort to reach a negotiated solution fails, then France will have to do what it takes by recognising without delay the Palestinian state. We are ready," Foreign Minister Laurent Fabius told parliament.

The parliamentary vote has raised domestic political pressure for the government to be more active on the issue. An IFOP poll showed 63 percent of French support a Palestinian state.

Fabius told deputies that, were they to adopt the motion, it would not change Paris' immediate diplomatic stance.

But he said that, after similar moves in Sweden, Britain, Ireland and Spain, Paris could not ignore the "never-ending" conflict that was playing into extremists' hands.

"There needs to be support, some would say pressure, from the international community to help the two sides make the final step to peace," Fabius said. Palestinians seek statehood in the Israeli-occupied West Bank and blockaded Gaza Strip with East Jerusalem as their capital - lands captured by Israel in a 1967 war.

The latest round of efforts to forge a two-state solution collapsed in April. Palestinians see little choice but to push unilaterally for statehood. Fabius said Paris was working to get a United Nations Security Council resolution adopted that would relaunch and conclude negotiations within two years. Diplomats have said France, Britain and Germany are preparing a text that could be accelerated if a separate resolution drafted by Palestinians, and calling for an end to Israeli occupation by November 2016, is put forward. "We must fix a calendar because without one how do you convince anybody that it won't just be another process?" Fabius said.

He proposed that in parallel a conference be held with regional actors, European Union, Arab League and major powers.

He did not specify at what stage France could decide to back a Palestinian state, but a diplomat said that it could happen anytime if Paris felt negotiations were dead.

AFP adds: The French minister's comments came as French lawmakers debated the non-binding motion urging the government to recognise Palestine as a state, amid growing European frustration at the moribund Middle East peace process.

The motion is expected to pass comfortably on December 2 when the lower house of parliament votes on the text proposed by the ruling Socialists.

The text of the motion "invites the French government to use the recognition of the state of Palestine as an instrument to gain a definitive resolution of the conflict".

The Socialist MP who drafted the text, Elisabeth Guigou, said the motion was "a message of peace and friendship addressed to the two peoples, Israeli and Palestinian."

"We want to contribute to the restarting of negotiations ... This is a alarm bell, so that tomorrow, it's not too late," she said.

But ahead of the vote, Israeli Prime Minister Benjamin Netanyahu warned France it would be making a "grave mistake" if it recognised Palestine as a state.

"Do they have nothing better to do at a time of beheadings across the Middle East, including that of a French citizen?" he told reporters in Jerusalem on November 23, referring to hiker Herve Gourdel who was executed by his jihadist captors in Algeria in September.

"Recognition of a Palestinian state by France would be a grave mistake," Netanyahu said.

Reflecting the sensitivity of the subject in France, parliament was divided, with the right-wing opposition UMP party expected to vote against the motion.

France was the scene of several pro-Palestinian demonstrations against Israel during this summer's 50-day offensive by the Israeli army in Gaza that killed more than 2,000 Palestinians and dozens of Israelis.

Some of these turned violent, with looters in July destroying Jewish business and shouting anti-Israel obscenities in the Paris suburb of Sarcelles - sometimes known as "Little Jerusalem" for its large community of Sephardic Jews.

The Jewish Agency for Israel, an advocacy group, said in September that more Jews had left France for Israel than from any other country in 2014, blaming a "climate of anti-Semitism."