A ban on US federal oil and gas leases would lead to job cuts and increase the nation's dependence on foreign energy sources, according to a new analysis by industry group the American Petroleum Institute (API).

The analysis, released less than two months ahead of a general election in which energy is expected to be a key topic of debate, found that a federal ban would cause offshore oil production to plummet by 44% by 2030, while offshore natural gas output would plunge by 68%.

The economy would also take a hit, causing US gross domestic product to decline by $700 billion and losing nearly 1 million jobs by 2022.

Former vice president Joe Biden, who is challenging incumbent US President Donald Trump in November's presidential election, has floated the idea of a moratorium on new federal oil and gas leases.

Earlier this year, Biden unrolled a $2 trillion clean energy plan to spur the installation of millions of solar panels and tens of thousands of wind turbines — including off the US coast — in his first four-year term.

'American jobs vs foreign jobs' - API

"Banning federal leasing and development on federal lands and waters would derail decades of US energy progress and return us to the days of relying on foreign energy sources hostile to American interests," API chief executive Mike Sommers said.

"This is ultimately a choice between American-made energy and foreign energy, a choice between American jobs and foreign jobs. It’s clear a federal leasing ban should be off the table — there’s far too much at stake for American workers, local economies and our nation’s energy security."

Trump, whose fossil fuel-friendly administration has rolled back key environmental rules and pulled the US out of the Paris Climate Agreement, has attacked Biden's plan, saying it would destroy jobs and increase the nation's reliance on foreign energy.

But Trump made a surprising about-face on Tuesday, extending by 10 years a ban on leasing offshore Florida in the eastern Gulf of Mexico and expanding it to include the state's Atlantic coast as well as that of South Carolina and Georgia.

The API attacked that decision, saying it was the wrong approach at the wrong time.

"Offshore access is critical for growing US energy leadership and providing affordable energy for American families for decades to come," API vice president of upstream policy Lem Smith said Tuesday.

"A ban on responsible energy development in the eastern Gulf and the South Atlantic puts at risk hundreds of thousands of new jobs, US energy security advancements and billions of dollars in critical revenue for states."