UNITED NATIONS — As powerful regional players renew their familiar calls for the elimination of Israel, a long-standing demand by Palestinian Arabs to establish an international force in Gaza is receiving new attention at the United Nations — and even in Jerusalem, where it was previously rejected out of hand.

The Palestinian Arab observer at the international body, Riyad Mansour, yesterday urged the U.N. Security Council to demand an end to Israel’s “blatant aggression” in Gaza, call for a cease-fire and establish an international “mechanism” to observe it.

In the past, Israel has steadfastly resisted repeated Arab attempts to establish such a force. But after last year’s war in Lebanon, Israel agreed to augment the U.N. Interim Force in Lebanon in the hope of ending the armed presence of an anti-Israel terrorist group, Hezbollah, on its border. The Israeli foreign minister, Tzipi Livni, recently started working on a plan to create a similar force that would enforce an end to weapons smuggling through Egypt’s border with Gaza, according to Israeli press reports.

A Jerusalem official who spoke on condition of anonymity told The New York Sun yesterday that any planning at the Foreign Ministry is merely at a “preliminary” stage.

At the United Nations yesterday, Mr. Mansour told reporters that “attacks” by Israel on Gaza and the “response” from the Palestinian Arab side should be “brought to an end.” He said Arab and Islamic countries would seek a meeting with Secretary-General Ban and the president of the Security Council to urge them to join the calls for a cease-fire between Israel and the Palestinian Arabs. This, he said, should later be followed by the establishment of a “mechanism of observers” to monitor such a cease-fire.

Israel objects to attempts to involve the council in its fight against Palestinian Arab militants. “The term ‘cease-fire’ is not really valid in this case,” the deputy Israeli ambassador to the United Nations, Daniel Carmon, told the Sun yesterday. “As a result of clashes between the different Palestinian factions, they decided to unite by attacking Israel,” he said. “If they can cease the fire among themselves, and then stop firing at Israel, we will end our defensive campaign, and no ceasefire would be needed.”

A U.N. envoy to the Middle East, Michael Williams, was also ambivalent about such a force. “I’m not sure” that UNIFIL is the right model for Gaza, Mr. Williams told Reuters in Jerusalem yesterday. “But I think that this is one of the things that we, the U.N., and Israel and the Palestinians need to be thinking about for the future.” While creating it would be a “hard task,” he said, “I have no doubt that if we came to that juncture, we could get such an international force.”

Regarding internal clashes in Gaza, Mr. Mansour told the Sun yesterday that that there should be no council intervention aimed at ending fighting between Hamas and Fatah, the main political Palestinian Arab rivals.

“This is a unfortunate internal issue that the Palestinian people under the leadership of President Abbas are working very hard, with the help if others, including the Egyptians, to bring it to an end,” he said. “I think that we succeeded to bring it to an end in the last few days, and we hope that it will prevail.”

But in Washington, the Bush administration’s security coordinator in Gaza characterized the situation more pessimistically yesterday: “An atmosphere of lawlessness exists in Gaza, with simple disputes often devolving into gunfights,” Lieutenant General Keith Dayton said. The internal conflict has spilled into Israel as hundreds of Kassam rockets were fired at Sderot and nearby communities, General Dayton told the Middle East and South Asia Sub-Committee of the House Foreign Affairs Committee.

These attacks were “a reminder that while Hamas’s intermediate target may be the Fatah-loyal forces of law and order in the Gaza Strip, the paramount goal for the rejectionists remains and will continue to be the destruction of Israel,” General Dayton said.

Mr. Mansour did not urge the council to call for ending clashes between Palestinian Arab factions. Nor did he, or his Arab and Muslim allies, call for the Lebanese army to end its deadly siege of a Palestinian Arab refugee camp, Nahr al-Bared, in Lebanon.

The Security Council is expected Friday to consider a resolution that would enforce an international tribunal to try suspects in the 2005 killing of a former Lebanese prime minister, Hariri.

Western officials yesterday dismissed calls by pro-Syrian politicians to drop the tribunal in order to appease Lebanon’s militants.

Prime Minister Siniora of Lebanon said yesterday that a group of “terrorists,” a group known as Fatah al-Islam, is “attempting to ride on the suffering and the struggle of the Palestinian people” by enforcing a siege of the Nahr al-Bared camp. To date, Fatah al-Islam spokesmen have failed to articulate clear demands beyond ending Israel’s “occupation,” according to reports.

In Iran, President Ahmadinejad predicted yesterday that Muslims would soon unite to “eliminate” Israel if it does not end its campaign of “criminality” around the Middle East.

Speaking in Isfahan, Iran, yesterday, Mr. Ahmadinejad also said his country would not stop enriching uranium, as the Security Council has demanded. Instead, he turned his ire to the “Zionist entity.”

“Advising the Zionists to stop 60 years of massacre, assassination, crime, and aggression, he said, ‘If you do not stop massacring, regional nations will soon come on the scene and eliminate you criminals,'” the government-owned IRIN news agency reported.