A pipeline explosion in northern Sinai has halted Egyptian gas exports to Israel and Jordan.
The gas could be cut off for up to two weeks while the pipeline, operated by Eastern Mediterranean Gas (EMG), is repaired, Sameh Fahmi, the Egyptian oil minister, said on state television.
Saturday's incident at El Arish in the north east of the Sinai peninsula was the work of foreign saboteurs, he said.
Israeli and Jordanian officials said they expected the gas supplies to remain halted for about a week.
In the meantime, Jordan has indicated it will weather the disruption by burning fuel oil and diesel for power generation.
Israel plans to use more gas from the Yam Tetis field off its southern coast, near the port of Ashkelon, until the Egyptian supplies can be restored. The country's national infrastructure ministry did not expect Israeli power supplies to be affected.
Television footage aired in Egypt showed flames shooting from the site of the pipeline rupture, upstream from the point where it branches to carry gas north to Israel and north east to Jordan and Syria.
The Egyptian army reportedly closed the main source of gas supplying the pipeline and was working to control the blaze. The explosion occurred as mass demonstrations against Hosni Mubarak, the Egyptian president, entered their 12th day.
"Saboteurs took advantage of the security situation and blew up the gas pipeline," a state television report said.
The Site intelligence group, which is based in the US and monitors websites, said some militant groups had been advocating attacks on the pipeline in the past few days.
However, Abdel-Wahhab Mabrouk, the governor of north Sinai, said he was relying on Bedouin leadership in the surrounding area "to help security apparatus with the investigation and give us hints of any other destructive acts".
He praised the response of pipeline engineers to the incident. "By closing the taps they contained the fire, and we assure the people there are no human losses."
Nevertheless, Egypt has declared a state of high alert in the area. Reports surfaced yesterday of gunfire aimed at a governorate building in northern Sinai and of a grenade attack on an empty church in Rafah, near the border with Gaza. Witnesses said Rafah's public library had been set on fire by members of disaffected groups in the area.
EMG, the joint venture between the state-owned Egyptian General Petroleum Corporation and the Israeli company Merhav, said the branch link between El Arish and Ashkelon had not been harmed but a metering station on the El Arish-to-Jordan pipeline had been damaged by fire.
The line to Israel has operated since 2008 and supplied 60 billion cubic feet of gas to the state in 2009 under a 15-year contract. Israel has been seeking alternatives to the gas imports, however, and is now expected to fast-track the development of recent large gas discoveries off its northern coast.
The pipeline disruption also comes at a politically tumultuous time for Jordan, which is without an energy minister as the country restructures its leadership. Last week, King Abdullah replaced his prime minister in the face of protests. Maruf Bakhit, the new prime minister, has been tasked with carrying out political and economic reforms.
Khaled Irani, a former Jordanian energy minister, said he had no long-term concerns about the potential for regime change in Egypt to disrupt Jordanian gas imports. "We have government to government agreement," he said. "It's a mutual benefit to Jordan and Egypt."
Jordan's reliance on Egyptian gas is also set to wane, as Qatar recently agreed in principle to export liquefied natural gas to Jordan.