WASHINGTON - The Quartet of Middle East peace mediators failed to announce any progress toward reviving Israeli-Palestinian peace talks after a lengthy meeting on Monday, while saboteurs bombed an Egyptian gas pipeline that supplies natural gas to Israel.

The group, which includes the European Union, Russia, the United Nations and the United States, ended a roughly two-hour and 15-minute dinner meeting in Washington without issuing a statement.

The Quartet wants to find a way to resume talks and to avert a diplomatic showdown expected at the United Nations in September, when the Palestinians may seek wider international recognition for a Palestinian state.

"There are still gaps that are impeding progress," said a senior Obama administration official who briefed reporters after the meeting on the condition of anonymity.

"There is a time and a place for public statements and there is a time and a place for private diplomacy," he added. "We need to do more work, privately, quietly, with the parties, in order to see if we can't close these gaps."

He declined to discuss the nature of the gaps and said the Quartet perceives "an urgent need to appeal to the parties to overcome current obstacles and find a way to resume direct negotiations without delay or preconditions".

US Secretary of State Hillary Clinton hosted the dinner, which was attended by European Union foreign policy chief Catherine Ashton, Russian Foreign Minister Sergei Lavrov, UN Secretary-General Ban Ki-moon and former British prime minister Tony Blair, a Quartet envoy. The core issues in the conflict include borders, security, the future of Jerusalem and Jewish settlements in territory Israel occupied in the 1967 Middle East War, and the fate of Palestinian refugees.

More than halfway through his four-year term, Obama has failed to bring Israel and the Palestinians into sustained talks to end their conflict and certain to miss a September target for a framework deal.

In the Sinai Peninsula, unidentified armed men bombed an Egyptian natural gas pipeline early Tuesday for the fourth time since February when former president Hosni Mubarak stepped down, cutting supplies to Israel and Jordan.

The blast occurred near the town of al-Arish in the north of the peninsula, it said, adding that the ensuing "flames were up to 10 meters high".

Egyptian national Nile television said flames could be seen up to 20 kilometers away. It gave no details on the causes of the explosion or the extent of the damage.

North Sinai Governor said the attack was a premeditated sabotaging act and similar to previous ones.

Reuters-Xinhua-AFP