Palestinian President Mahmoud Abbas swore in an emergency Cabinet on Sunday and outlawed the militia forces of the Islamic Hamas movement, deepening the violent rupture in Palestinian society.

Hamas seized control of Gaza last week after routing Abbas' Fatah movement. The violence has left the impoverished coastal strip increasingly isolated, a situation worsened Sunday when an Israeli fuel company cut off deliveries to gas stations there.

The hurried swearing-in ceremony of the new Cabinet left the Palestinians effectively with two governments — the Hamas leadership in Gaza and the new Cabinet in the West Bank led by respected economist Salam Fayyad.

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Abbas issued decrees Sunday annulling a law requiring the new government to be approved by parliament, which is dominated by Hamas, and outlawing the Islamic group's militias.

"There is one authority, one law and one legitimate gun in all areas of our homeland, in the West Bank and Gaza," he said later.

In Gaza, deposed Prime Minister Ismail Haniyeh — who has ignored Abbas' order firing him — called the new government illegal and insisted he remains in power. "The council of ministers considers the steps adopted by President Mahmoud Abbas to ... have no basis in law," he said. "The national unity government asserts here that we are fulfilling our duty according to our law."

In an apparent response to Abbas' decree, Haniyeh fired the head of internal security and the director general of the Palestinian police, Hamas-allied Al Aqsa TV said. The decisions were symbolic because both men moved to the West Bank.

Fayyad, an independent, will retain his post as finance minister and also serve as foreign minister in the emergency government, which Abbas appointed to replace the Hamas-led Cabinet he fired after Hamas seized control of Gaza.

The small emergency Cabinet is dominated by independents, including human rights activists and business people. Only one, Interior Minister Abdel Razak Yehiyeh, is a member of Abbas' Fatah movement.

In taking office, Fayyad said the new government would work to end the chaos and provide security for the Palestinians. "We are going to work with clean hands, systematically," he said.

Addressing the Palestinians in Gaza, he said: "You are in our hearts, and the top of our agenda."

It is "time to work together for Palestine," he said.

Israeli Prime Minister Ehud Olmert said the new Palestinian government would create a "new opportunity" for the peace process. Olmert has long welcomed Abbas as a negotiating partner, but said Abbas' now defunct alliance with Hamas had made peacemaking virtually impossible. Israel considers Hamas, which has killed hundreds of Israelis in suicide bombings, a terrorist group.

"We have a new opportunity ... that we haven't had in a long time," Olmert told reporters shortly before leaving for the United States. "A government that is not Hamas is a partner."

In the showdown, much of the international community, including the U.S., the European Union and moderate Arab states, is backing Abbas. Declarations of support were likely to be followed soon by a resumption of foreign aid to the Palestinian Authority.

The U.S. consul general in Jerusalem, Jacob Walles, met with Abbas on Saturday and said the embargo is expected to be lifted once the new government was sworn in.

But the money is unlikely to reach Gaza, where panicked residents stocked up, fearing growing shortages of food, fuel and other staples as the crossings of the fenced-in strip with Israel and Egypt remained closed.

The Israeli fuel company Dor Alon said Sunday it was cutting of fuel supplies immediately to Gaza's gas stations. The company is the sole provider of gasoline to Gaza.

Dor Alon will continue to ship fuel to Gaza's electricity power plant, the company said, but about 30 percent of Gazans have been cut off from the electric grid because of infrastructure damage caused by the fighting and they rely upon generators for power.

Palestinian Health Ministry officials said they hoped that hospitals currently running on generators would be reconnected to the grid before their fuel reserves run out, but even if they do, a gasoline shortage would immobilize ambulances and prevent deliveries of blood, medicine and food to medical facilities.

Palestinian official Saeb Erekat said he had appealed to Israel and the international community not to cut off supplies to Gaza. "Residents must not be punished for the bloody coup staged by Hamas," he said.

Hundreds of Gazans spent the night sleeping at the Erez border crossing with Israel, hoping to escape Hamas rule.

Jamal Abu Zayda, a pro-Fatah security official and one of the few who was allowed to cross Sunday morning, said Israeli solders fired rubber bullets, tear gas and concussion grenades into the crammed concrete corridor to try subdue the unruly crowd.

"It's a problem letting people through under these circumstances, there's nobody on the other side, and it's a potential security risk," said Shlomo Dror, an Israeli military spokesman.

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