Britain on Thursday warned against the threat of protectionism as it slammed the United States for leading a "distortive" green energy subsidy race.

Finance Minister Jeremy Hunt's remarks came as his government updated its energy security plan to ramp up renewable and nuclear power.

The Conservative government led by Prime Minister Rishi Sunak is targeting "net zero" carbon emissions for the UK by 2050.

"We are not going toe-to-toe with our friends and allies in some distortive global subsidy race," Chancellor of the Exchequer Hunt wrote in The Times newspaper.

"With the threat of protectionism creeping its way back into the world economy, the long-term solution is not subsidy but security."

President Joe Biden's $370-billion program of subsidies for green energy, as well as tax cuts for US-made electric cars and batteries, seeks to accelerate the country's transition to low-carbon.

Yet it has strained relations with Europe, prompting the 27-nation European Union to unveil its own measures.

Britain will "continue to back industries of the future" and "target public funding in a strategic way in the areas where the UK has a clear competitive advantage", Hunt added Thursday as it further detailed its previously-announced green plans.

World powers are seeking to tackle climate change but also increase energy independence and lower electricity and gas bills, which rocketed after key producer Russia invaded Ukraine last year.

"Transforming our energy system is no longer just about tackling climate change, it is also a matter of national security," Hunt added.

"To protect ourselves from future price spikes, we need to accelerate the move to cleaner, cheaper, home-grown energy."

The UK government's multi-billion-pound "net zero" plan seeks to boost investment in cleaner energy such as wind, solar and nuclear.

It includes a £20-billion ($25-billion) investment in emerging technology to capture carbon and store it underground, as well as more funds for emerging floating offshore wind power and green hydrogen.

The plan also accelerates nuclear power, which could supply one quarter of UK electricity by 2050 compared with 15 percent currently.

The opposition Labour party claimed the government's update Thursday lacked new cash, while environmentalists denounced it as a "lacklustre" set of climate policies.