NEW YORK — Amid a last-ditch push to salvage his peace efforts between Israel and the Palestinians, Israeli Prime Minister Ehud Barak this week asked a unique gathering of world leaders here to play an active role in the Middle East peace process.

Speaking to more than 150 heads of state at the U.N. Millennial Summit on Wednesday, Barak said Israel is prepared to accept less than 100 percent "of its dreams."

Israel has demonstrated a willingness to "make painful decisions for the sake of peace," he said, citing as examples the negotiations with Syria and the Palestinians and the complete withdrawal from southern Lebanon.

Barak called on U.N. member states to encourage reconciliation and discourage or oppose any unilateral measures — a reference to Sept. 13, when Palestinian Authority President Yasser Arafat has threatened to declare statehood. Palestinian officials, however, have indicated that the declaration will be postponed.

His public comments came as he engaged in some private diplomacy as well. The U.N. speech came after meetings with Cuban President Fidel Castro, Indonesian President Abdurrahman Wahid and South African President Thabo Mbeki, and preceded consultations with President Clinton and French President Jacques Chirac.

Politically embattled at home, Barak's visit here is being seen as his last attempt to achieve a peace deal following the collapse of the Camp David summit in July, when neither side could agree on Jerusalem's future.

But more significant for Barak than the uncertain Sept. 13 is the end of October, when the Knesset reconvenes from its summer recess. At that time, the viability of his already weakened coalition will be put to the test.

Clinton met Wednesday afternoon separately with Barak and Arafat, apparently in an effort to see if there was enough movement to warrant future negotiations.

Following Clinton's meeting with Barak, the Israeli side said it expected the U.S. president and other world leaders to press Arab states in the next 48 hours to encourage Arafat to show greater flexibility on Jerusalem.

In his six-minute speech to the assembled dignitaries, Barak singled Arafat out by name, who was seated in the audience behind a placard bearing the name "Palestine."

"We are at the Rubicon, and neither of us can cross it alone," Barak said in his measured and staccato English.

"History will judge what we do in the next days and weeks: Were we courageous and wise enough to guide our region across the deep river of mistrust, into a new land of reconciliation? Or did we shrink back at the water's edge, resigned to lie in wait for the rising tide of bloodshed and grief?"

Barak had opened his speech by reciting, in Hebrew then in English, the famous biblical "beat their swords into plough shares" quote from the prophet Micah.

He went on to state both the centrality of Jerusalem in the history and faith of the Jewish people, and its spiritual and emotional connection to other peoples of the world.

"Jerusalem, the eternal capital of Israel, now calls for a peace of honor, of courage, and of brotherhood," said the Israeli premier.

"We recognize that Jerusalem is also sacred to Muslims and Christians the world over, and cherished by our Palestinian neighbors. A true peace will reflect all these bonds. Jerusalem will remain united and open to all who love her."

Throughout Barak's speech, Arafat looked on impassively.

In his speech a short while later, the Palestinian Authority president said: "We remain committed to our national rights over East Jerusalem, capital of our state and shelter of our sacred sites, as well as our rights on the Christian and Islamic holy sites."

Arafat countered that his people, too, had made concessions, agreeing to establish a state "on less than a quarter of the historical territory of Palestine."

He added: "We have made a strategic decision committing ourselves to the peace process, offering significant and painful concessions in order to arrive at a reasonable compromise acceptable to both sides."

Meanwhile, an adviser to Arafat said that this week's talks will prove decisive.

"Either we reach a formula that we can build on and negotiations resume, or we reach a deadlock," said Nabil Abu Irdeineh.

Since the failure of the Camp David summit, both sides have accused the other of intransigence and sought international backing for their positions.

When it comes to prospects for the Israeli-Palestinian peace accord, Barak remains cautious.

"I do hope, and I pray," he told reporters outside the United Nations. "But I don't know."