The dotted line in this map shows the route of the gas pipeline.

A pipeline carrying gas from Egypt to Israel and Jordan has been hit by an explosion in the Sinai peninsula.

The explosion on Monday sent flames into the sky, but there were no immediate reports of casualties. Emergency services were deployed to control the fire.

The blast took place at a pumping station along the pipeline at Nagah, in the Bir Abdu region, sources told the Reuters news agency.

The news agency quoted an official as saying that men armed with machine guns came in a small truck and forced guards at the station to leave before planting explosive charges.

Gasco, the company which operates the pipeline, shut it down after the explosion. 

This is the third attack on Egyptian gas pipelines since an uprising overthrew Hosni Mubarak, the country's president, and saw power being handed over to the military. The first two took place on April 27 and February 5.

There was also a failed attempt to attack the pipeline in March.

Egypt supplies about 40 per cent of Israel's natural gas, where it is used mainly to generate electricity. In December 2010, four Israeli firms signed 20-year contracts worth up to $10bn to import Egyptian gas.

Jordan, meanwhile, imports about 6.8 million cubic metres of Egyptian gas every day, accounting for 80 per cent of its electricity requirements.

Revision of contracts

In April, Essam Sharaf, the Egyptian prime minister, asked for the revision of all contracts to supply gas abroad, including to Israel.

Sharaf said the contracts would be revisited so the gas "would be sold with deserved prices that achieve the highest returns for Egypt".

The controversial gas deal with Israel has been repeatedly challenged in Egyptian courts on the grounds of its secretive clauses and because it was done without parliamentary consultation.

A court imposed an injuction on the deal, in a move ignored by Mubarak's government. A higher court overturned the freeze in 2010, on condition the government regulate the quantity and price of gas exported.

In May, Jordan said Egypt was withholding its contracted gas supply to energy-poor Jordan unless a new deal was signed at a higher price.

Under a 14-year deal signed in 2002, Egypt used to sell gas to Jordan at a discounted price - half of the market price, or $3 per million British Thermal Units.