Rachel Reeves has reassured British Steel workers that the government would look at nationalising the firm if required.
Concerns are growing among ministers that the blast furnaces at the Scunthorpe could run out of raw materials within days, the BBC reports.
Reeves is reported to have told trade unions the government is aware of the strategic importance to the UK of the steel industry.
Donald Trump recently imposed a 25% tariff on imports of steel to the US.
And British Steel has warned its furnaces in Scunthorpe are "no longer financially sustainable", risking around 2,700 jobs without government support.
British Steel has been owned by Chinese firm Jingye since 2020, which says it has invested over £1.2billion to keep the plant running, incurring a daily loss of £700,000.
Speaking to MPs at the Commons Liaison Committee, Sir Keir Starmer said all optioned "remain on the table" when asked about government support, adding: "I'm absolutely committed to steel production in this country."