The boss of Rolls-Royce has issued a stark warning that Britain is at risk of missing out on creating a homegrown industry for mini-nuclear reactors, repeating a failure to capitalise on its lead in offshore wind, if the first projects are not approved before the end of the year.

Tufan Erginbilgic said the UK had the chance to gain a “first-mover advantage” by becoming one of the first nations in the world to award government contracts for small modular reactors, but it needed to “action it fast” to ensure that the parts required for construction would be manufactured domestically.

“The UK has missed the opportunity to develop the offshore wind supply chain,” Erginbilgic said. “This will be in that category.”

Britain is second only to China in terms of installed offshore wind capacity, but most of the critical components for wind turbines are made overseas. “Only as the first mover will [you] enable the supply chain,” the Rolls-Royce chief executive said.

Six designs for small modular reactors, including one from Rolls-Royce, have been selected to compete for up to £20 billion in taxpayer funding. The deadline for competitors to submit details of their bids, including costs and timeframes for the projects, was pushed back by two weeks, to July 8, at the request of one of the American candidates.

The selection process is being led by Great British Nuclear, an arm’s-length body set up by the government last year to drive the deployment of nuclear power. Great British Nuclear is planning to whittle down the contenders to a list of four later this summer, before selecting the final two developers by the end of the year. It had been hoped previously that contracts with developers of small modular reactors would be signed this summer. The first small modular reactor is not expected to be up and running before 2035.

The outspoken FTSE 100 chief executive is leading a turnaround of Rolls-Royce, including cutting its debts and improving margins, calling the 118-year-old British company “a burning platform” whose future had been in doubt upon his arrival.

Erginbilgic, 64, said he was “very confident” that Rolls-Royce’s design would be picked as one of the first to be given the go-ahead. The company had already held early talks with suppliers, including some in Britain, he said. If selected, it would look to make a final investment decision towards the end of the decade.

EDF, of France, and four players from the United States — Holtec, NuScale, Westinghouse and GE Hitachi — also have made the shortlist to deploy their small modular reactor technologies in Britain.

Unlike conventional plants, small modular reactors can be factory-built, take up the space of one or two football pitches and have a capacity of up to 500 megawatts.

The government has set a goal of having up to a quarter of Britain’s electricity coming from nuclear power by 2050, up from about 13 per cent at present. Most of the country’s existing plants are set to close by the end of the decade. EDF is building Britain’s only new nuclear power station, Hinkley Point C in Somerset, which would generate 3.2 gigawatts. However, the project has been beset by delays and budget overruns.

A spokesman for the Labour Party said: “Labour supports small modular reactors as part of our future energy mix and will work with the industry to deliver the new nuclear our country needs.”

The Conservatives have promised to approve two new fleets of small modular reactors within the first 100 days of the next parliament.