Eager anticipation of the next American president offering a dramatically different policy on climate change is being tempered by the chill winds of the financial crisis.

Barack Obama or John McCain will inherit a blighted economy, a ballooning deficit set to reach $1 trillion and a political landscape in upheaval from the market turmoil of recent weeks.

Environmental groups are already bracing themselves for delays or disappointment on action to tackle global warming which, they say, will inevitably be seen as having an impact on American jobs.

Steve Clemons, a director at the liberal think-tank The New America Foundation, said that whoever succeeds President Bush is “going to have a horrible time”. He added: “They are not going to be able to do everything they said they were going to do. The economic constraints were always going to be huge, even before the current crisis. Now, with the drama over the financial markets, when the next president is sitting behind the desk of the Oval Office he will have to weigh up different programmes, cut back and pare down.”

Already there is talk of plans for universal healthcare or expensive tax cuts being reconsidered, while Britain is among the international governments alarmed over what the crisis may mean for hopes of getting a breakthrough deal on climate change. Mr Obama has proposed cuts in greenhouse gas emissions of 80 per cent by 2050 and wants to fund a ten-year, $150 billion energy independence programme by selling carbon-use permits to industry through a European-style cap and trade system. Mr McCain is not far behind, promising cuts of 60 per cent by 2050.

Diplomats acknowledge that the prospects of securing Congressional agreement for such measures are diminished. Gordon Brown is known to be concerned about how little time the next president will have to focus on the issue before heading to Copenhagen in December next year where a new international treaty on climate change will be negotiated.

The last such summit produced the Kyoto Protocol that Mr Bush rejected because it would disadvantage American workers unfairly against those in China and India.

A bi-partisan effort to introduce significant cuts in America’s carbon use failed to pass the Senate this year and state-wide measures have recently been marked by their modesty. In Michigan, for example, legislation was introduced to reduce greenhouse gas emissions by just 6 per cent over the next 12 years.

Even though Democrats — who are more inclined to fight global warming — are expected to tighten their grip on Capitol Hill after the elections in November, they will still encounter opposition from Rust Belt states and those heavily reliant on coal, as well as lobbying from industry and unions.

“Right now, I don’t think that will be our primary concern,” said Hank Cox, of the National Association of Manufacturers. “If a truck is coming straight at you, that’s your main worry, not the truck coming round the bend that might get to you eventually.

“The next thing is getting consumers out of their lairs to start consuming again.” Against these, carbon emission schemes are a distant concern, Mr Cox said. “If the economy remains in the same suspended animation that it is now, there will be a reluctance to undertake any expensive new legislative regimes.”

Frank O’Donnell, of Clean Air Watch, said: “The state of economic turmoil throws up a whole new question mark over climate change legislation. It was already an uphill struggle and the state of the economy has made the angle of that hill even steeper.

“I’m not expecting any economic-wide effort to introduce the cap and trade measures to come bouncing on to the Senate floor any time soon. It’s like turning a great battleship around. I know the next president will have to ease it around in the right direction.”

The British Government has spent more than three years paving the way for the next president by chipping at the road block the US has long represented on getting a binding agreement — designed to “penetrate every layer of American society”.

Dozens of MPs have been dispatched to sell the virtues of a cap and trade system to state legislatures, while the Bishop of Liverpool, the Right Rev James Jones, has preached the environmental stewardship of God’s creation to evangelical leaders of the Religious Right.

The TUC and the CBI have told their American counterparts how new jobs — and fortunes — can be found in carbon-efficient technology. Retired American generals have been lectured about the security implications of being too reliant on Middle Eastern oil.

Even the Royal Family has got involved, with the Prince of Wales lobbying Congress and the White House on the issue. Mr Obama will send observers to the climate change conference in Poland in December and Susan Rice, his foreign policy adviser, told The Times: “This will remain one of our priorities.”

John Ashton, the British special representative on climate change, said: “We’ll have to fight harder.”

The British Embassy in Washington said that extra staff had been hired to prepare for a new offensive on climate change. “Both candidates are talking about the energy crisis, and that is encouraging. We have to be very focused on the benefits that green jobs can bring. The economic turbulence will mean people focusing very hard on whether they can afford to do it — we will say they cannot afford not to.”

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