“Together, we’re committing to collectively reduce our methane by 30 per cent by 2030. And I think we can probably go beyond that,” Biden said at the summit. “It’s going to boost our economies, saving companies money, reducing methane leaks, capturing methane to turn it into new revenue streams, as well as creating good paying union jobs for our workers.”

Among the new signatories was Brazil – one of the world’s biggest emitters of methane. The pledge now includes six of the world’s 10 biggest methane emitters: the United States, Brazil, Indonesia, Nigeria, Pakistan and Mexico.

China, Russia, India and Iran, also top-10 methane emitters, have not signed up. Those countries were all included on a list identified as targets to join the pledge.

Since it was first announced in September with a handful of signatories, the United States and European Union have worked to get the world’s biggest methane emitters to join the partnership.

There were roughly 60 countries signed up only last week, after a final diplomatic push from the United States and EU ahead of the COP26 summit.

While it is not part of the formal UN negotiations, the methane pledge could rank among the most significant outcomes from the COP26 conference, given its potential impact in delaying disastrous climate change.

A UN report in May said steep cuts in methane emissions this decade could avoid nearly 0.3 degrees Celsius of global warming by the 2040s. Failing to tackle methane, however, would push out of reach the 2015 Paris Agreement’s objective to limit the global rise in temperature to 1.5 degrees above pre-industrial levels and avoid the worst impacts of climate change.

The 30 per cent methane cut, which is not legally binding, would be jointly achieved by the signatories, and cover all sectors. Key sources of methane emissions include leaky oil and gas infrastructure, old coal mines, agriculture and landfill sites.

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First COP26 pledge: world leaders agree to end deforestation by 2030

First COP26 pledge: world leaders agree to end deforestation by 2030

If fulfilled, the pledge is likely to have the biggest impact on the energy sector, since analysts say fixing leaky oil and gas infrastructure is the fastest and cheapest way to curb methane emissions.

The United States is the world’s biggest oil and natural gas producer, while the EU is the biggest importer of gas.

The United States on Tuesday unveiled its own sweeping proposal to crack down on methane emissions with a focus on the oil and gas sector. The main regulation could take effect as soon as 2023 and slash methane from oil and gas operations by 74 per cent from 2005 levels by 2035, according to the US Environmental Protection Agency.

The EU and Canada both plan to unveil methane legislation addressing the energy sector later this year.