Fears were growing today for hundreds of British Steel jobs as ministers came under mounting pressure to thrown the firm a lifeline.
The Government is considering a multimillion-pound rescue package for the struggling business.
But reports emerged today that 800 workers could be made redundant by the Chinese-owned company.
Job losses would focus mainly on the plant in Lincolnshire, according to Sky News.
British Steel refused to comment when asked about potential cuts.
Community steelworkers' union national officer Alun Davies said: "We are extremely concerned about the reports that British Steel is looking to cut hundreds of jobs.
"This move would represent a betrayal of their loyal workforce and their commitments to invest in the business.”
He added: "Steelworkers played their part to protect our steel industry and are being failed by both the Government and British Steel who are abdicating their responsibilities to the workforce and our country.
"British Steel should urgently clarify its position and know that we will use any means at our disposal to fight this dangerous plan."
Shadow Business Secretary Jonathan Reynolds said: “This is deeply worrying news for British Steel workers and their families who need urgent clarity on the future of the site.
“Endless sticking plasters from the Conservatives have left our UK steel sector on the brink.
“Britain needs a long-term solution not just another bailout with no plan to keep UK steel internationally competitive or deliver a return on taxpayers’ investment.”
The Government is reportedly considering cash injections into both British Steel and Tata Steel UK.
Chancellor Jeremy Hunt was said to be close to signing off on a support package, which could funnel around £300million to British Steel, with an "equivalent" sum going to Tata.
Ministers were said to have demanded the companies agree to protect jobs if they wanted the Government handout.
UK steel firms have repeatedly warned about the existential threat to the industry because of high energy costs.
They have called for help in switching to more environmentally friendly production methods, amid pressure to slash emissions.
Prime Minister Rishi Sunak's spokesman said today: "Any reports of prospective job losses would be of concern.”
He insisted the Government “always stands ready to provide or signpost assistance for anyone who needs it”.
He added: "In terms of long-term support for UK steel, this is a Government that has taken a number of steps in this space."
Last month, 440 jobs at Liberty Steel were plunged into jeopardy.
Writing exclusively for mirror.co.uk , Liberty Steel’s chief transformation officer Jeff Kabel warned a “revolution” was needed to save an industry “on life support”.
The UK steel industry employs 34,500 staff directly and supports another 43,000 in supply chains.
The Mirror has been campaigning to Save Our Steel since 2015.
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