The Norwegian giant will join Italy's Eni, Pemex of Mexico, BG Group of the UK, Thailand's PTTEP and Houston-based Southwestern Energy in forming the Climate and Clean Air Coalition (CCAC) Oil & Gas Partnership, an effort to foster transparency and share best practices in tackling methane reduction.

"Fighting climate change is vital," Lund said in a statement. "More than 80% of greenhouse gas emissions are linked to the use of fossil fuels. Statoil has a clear objective — to be recognised as the most carbon-efficient oil and gas producer in the world."

A dozen national governments have also signed onto the pact, including the US, which played a key role in getting the companies to agree, according to reports. Other countries include Canada, France, Mexico, Nigeria, Norway, Russia and the UK.

Environmentalists were dubious of the pact. Friends of the Earth International accused the companies of "greenwashing their dirty image".

"This pact is just one additional half-baked corporate measure, a drop in the ocean when it comes to saving the climate," said the group's climate justice and energy co-ordinator Dipti Bhatnagar.

Methane, the main component of natural gas, is a greenhouse gas said to be 20 times more potent than carbon. It escapes from upstream operations either through flaring or in the process of transportation and compression.

While natural gas is thought to be an important fuel to help reduce global emissions, critics say emissions of raw methane into the atmosphere could eliminate any gains made from burning the relatively cleaner hydrocarbon.

The agreement does not set any targets for reducing methane emissions, nor does it make any mention of reducing production of oil and gas. Rather, partners commit to a framework for forming a "road map" to cut methane emissions.

Southwestern Energy executive vice president Mark Boling said the companies agreed to use the latest technologies in production to ensure that gas leaks are contained.

"We want, basically, to get more companies internationally that recognise that there are cost-effective ways to reduce methane emissions in the upstream sector," Boling told the Wall Street Journal.

Statoil is a major producer in the Bakken shale play in North Dakota. The US state has made a concerted effort to force producers to capture natural gas associated with oil production rather than flare it. A larger percentage of gas is flared in North Dakota than in any US state.

Lund announced the partnership on Tuesday at the UN Secretary General’s Climate Summit in New York.

He also voiced Statoil's "strong support" for a carbon price.

Online

Statoil joins pledge to reduce methane