Great British Energy would be modelled on France's EDF and other firms owned by foreign states operating in the UK.

It would aim to ensure a massive expansion in clean energy planned by Labour will deliver British jobs and greater energy security.

The Labour leader unveiled the plan to applause in his conference speech.

Great British Energy would be set up with public money but would be independently operated and any profits would be reinvested, Labour sources say.

It would be able to build new wind, wave and solar projects - but also invest in privately-owned renewable schemes.

It would start out as a small scale generator, and build up market share as it invests in new projects, the party says. Labour sources say they see no reason why the company could not eventually grow to establish itself as "a significant, credible generator in a competitive market".

The planned new company would not be able to guarantee every job created in the push for clean energy is British.

But Labour hopes it will act as a "national champion" to rival firms like French-owned EDF, which employs more than 10,000 people in the UK.

"Labour will make sure that the public money we spend building up British industry spurs on private investment, stimulates growth … and the British people enjoy the returns," said Sir Keir in his conference speech.

"Labour won't make the mistake the Tories made with North Sea oil and gas back in the 1980s. Where they frittered away the wealth from our national resources."

The largest onshore wind farm in Wales is owned by Sweden, meaning "energy bills in Swansea are paying for schools and hospitals in Stockholm," he added.

"The Chinese Communist Party has a stake in our nuclear industry. And five million people in Britain pay their bills to an energy company owned by France."

The start-up money for the company would come from a new Sovereign Wealth Fund announced by shadow chancellor Rachel Reeves on Monday.

Sir Keir has resisted calls from trade unions and many on the left of his party to nationalise the energy industry to help keep soaring bills down, arguing instead for an extension of the windfall tax on their profits.

He has already announced plans to make the UK the first major economy to generate all of its electricity without fossil fuels.

He says this can be achieved by 2030 - five years earlier than being planned by the government.

"The road to net-zero is no longer one of stern, austere, self-denial," he said in his speech.

"It's at the heart of modern, 21st century aspiration. Technology has turned everything on its head. Green and growth don't just go together - they're inseparable.

"The future wealth of this country is in our air, in our seas, and in our skies. Britain should harness that wealth and share it with all."