“We will stand behind this symbol of Scotland’s industrial brilliance,” Starmer told the Scottish Labour conference in Glasgow.
Starmer, who won an election last year pledging to move towards clean energy, said there was a “huge opportunity for renewal” at the site, which could have a future in biofuels or hydrogen energy, for example.
The government also announced funding for retraining workers and was looking to “identify a viable, low carbon industrial future” for Grangemouth, according to a statement.
The transition to renewable power “must be managed pragmatically” said Starmer, adding that “the oil and gas in our waters is also vital for our security”.
“Oil and gas will be part of the future in Scotland for decades to come,” added Starmer, whose Labour government has planned to ban new oil and gas exploration in the North Sea.
Unite, one of the two biggest trade unions which has campaigned against the refinery’s closure, welcomed the announcement as a “step forward in the right direction”.
The UK and Scottish governments already pledged £100m in 2024 to create jobs in the Grangemouth area by “investing in local energy projects”.
Britain’s last coal-fired power station closed last year in a landmark move as the country races to phase out fossil fuels.
The British government is also planning to end the sale of petrol and diesel cars by the end of the decade.
However, there are concerns oil-generating nations like Scotland will struggle to move towards renewables while protecting workers in fossil fuel industries.
In New Zealand, Prime Minister Christopher Luxon said the coalition Government was considering whether to build a new oil refinery amid the country’s energy production challenges.
Luxon’s remarks on Friday were made ahead of the expected release of a government report investigating New Zealand’s fuel resilience, including the potential re-opening of the Marsden Point oil refinery.
© Agence France-Presse. Additional reporting: NZME