Todd Stern claims the world will have to forgo developing reserves of oil, coal and gas in order to solve global warming

The world’s fossil fuels will “obviously” have to stay in the ground in order to solve global warming, Barack Obama’s climate change envoy said on Monday.

In the clearest sign to date the administration sees no long-range future for fossil fuel, the state department climate change envoy, Todd Stern, said the world would have no choice but to forgo developing reserves of oil, coal and gas.

The assertion, a week ahead of United Nations climate negotiations in Lima, will be seen as a further indication of Obama’s commitment to climate action, following an historic US-Chinese deal to curb emissions earlier this month.

A global deal to fight climate change would necessarily require countries to abandon known reserves of oil, coal and gas, Stern told a forum at the Center for American Progress in Washington.

“It is going to have to be a solution that leaves a lot of fossil fuel assets in the ground,” he said. “We are not going to get rid of fossil fuel overnight but we are not going to solve climate change on the basis of all the fossil fuels that are in the ground are going to have to come out. That’s pretty obvious.”

Last week’s historic climate deal between the US and China, and a successful outcome to climate negotiations in Paris next year, would make it increasingly clear to world and business leaders that there would eventually be an expiry date on oil and coal.

“Companies and investors all over are going to be starting at some point to be factoring in what the future is longer range for fossil fuel,” Stern said.

The UN, in its landmark IPCC climate science report last year and in another report earlier this month, warned that the world is close to blowing through a carbon budget, which would lead to warming of above 2C.

The UN Environment Programme warned last week that global emissions must peak in the next decade, fall by half by 2050, and then decline to zero to remain within that budget.

Obama said in an interview last June that the US was going to have to start getting off fossil fuel - but he has also simultaneously pursued an “all of the above” energy strategy that has ramped up domestic oil and gas production.

In an interview for the Year of Living Dangerously series, Obama said: “We’re not going to be able to burn it all. Over the course of the next several decades, we’re going to have to build a ramp from how we currently use energy to where we need to use energy. And we’re not going to suddenly turn off a switch and suddenly we’re no longer using fossil fuels, but we have to use this time wisely, so that you have a tapering off of fossil fuels replaced by clean energy sources that are not releasing carbon … But I very much believe in keeping that 2C target as a goal.” Such statements, coupled with Obama’s support for natural gas industry, have frustrated and confused some campaigners.

At the same time, Obama has pursued an ambitious domestic and international climate change agenda – despite opposition from Republicans who now control both houses of Congress after the mid-term elections.

In a surprise announcement, Obama and his Chinese counterpart, Xi Jinping, announced last week they would take steps together to curb emissions.

A few days later, on the eve of the G20 summit in Brisbane, Obama announced the US would give $3bn to an international fund to help poor countries cope with climate change.

Stern, in comments to reporters following his appearance, said the moves had helped to build momentum ahead of the meetings in Lima. “You are not suddenly going to make the hard issues all vanish,” he said. “I don’t know whether you are going to see any shift in Lima, for example.”

China and other countries would be watching closely to see whether Obama can move forward, with the Republican leadership in Congress already threatening to block the main pillar of his climate plan, cutting carbon pollution from power plants.

But the envoy said the deal between the world’s two biggest carbon polluters – and antagonists as Stern called them – had improved the atmosphere going into the last stretch of negotiations for reaching a climate deal in Paris at the end of next year.

“We will see what transpires but this is a very big step,” he said. “Generally if you are holding stock in the Paris negotiations your stock will have gone up after this announcement.”