Steelworkers from across Britain march on Parliament pleading with MPs to save the “crumbling” industry.
Hundreds of staff are expected to rally in Trafalgar Square before processing to Westminster just before Prime Minister’s Questions on Wednesday.
They want to highlight the threat to the UK’s £2.4billion sector, which employs 34,500 people directly and supports another 43,000 in supply chains.
Community union general secretary Roy Rickhuss said: “Britain needs its steel industry; our country is made from it - the roads we drive, the bridges we cross, the hospitals that heal us and the schools our children learn in.
“But the UK Government must decide whether it wants a steel industry in this country.
“In the absence of government backing, we face Britain’s proud history of steelmaking coming to an end.”
Firms are desperate for ministers to throw the sector a lifeline to help it switch to more environmentally-friendly production as Britain’s race to net-zero intensifies.
Steel is blamed for 14% of the UK’s industrial emissions and 2.7% of all Britain’s greenhouse gases.
Ministers and industry chiefs have been locked in negotiations about funding to help the sector move to less-polluting production.
But bosses are increasingly frustrated by what they say is a lack of urgency from the Tories over funding the “green steel transition” and easing sky-high electricity prices hammering companies.
Trades Union Congress general secretary Paul Nowak said: “It's time the UK Government stepped up and invested in our steel industry to make it carbon free.
“This would protect the good quality jobs that families depend on in our industrial heartlands and it would boost the UK economy at the same time as ending emissions to keep our climate safe.
“We stand at a crossroads, choosing between the crumbling of the British steel sector or a rapid, exciting move to net-zero steelmaking.
“We need Government leadership, support and partnership more now than ever.”
Gareth Stace, director general of trade body UK Steel, warned Britain was “lagging behind” rival countries in moving to green steel.
“We can only make the necessary billions of pounds of investment if our government fully backs UK steel production - and it is now or never to make that decision,” he said.
“Otherwise, we will watch other steelmaking nations invest, overtake us, and witness our steel sector become a thing of the past.”
Labour MP Stephen Kinnock, whose Aberavon constituency includes Britain’s biggest steelworks, Tata at Port Talbot, blasted the Government for not doing more.
Mr Kinnock, who chairs the All Party Parliamentary Group on Steel, said: “Global demand for steel is going up and Britain deserves a piece of the pie, but we will only seize the huge opportunities that are out there if the Government partners with steel firms to help them decarbonise and get ahead of the competition.”
Workers from Britain’s steel-producing firms - Tata Steel, British Steel, Liberty Steel, Celsa Steel, Marcegaglia and Sheffield Forgemasters - are due to be on tomorrow’s march.
Mark Davies, chairman of the Steel and Wire Committee at Tata’s Port Talbot plant, said: “Steel is integral to our communities - it’s not just us and our families who rely on steelworkers pay cheques, it’s our whole communities.”
Community’s assistant general secretary Alasdair McDiarmid said: “With the Government’s backing we could see a thriving steel industry at the heart of the British economy, building the foundations of a greener, better Britain.
“Without the Government’s backing we will see our steel industry diminish, damaging our economy and every single community that depends on steel.”
The Mirror has been campaigning to Save Our Steel since 2015.
A Department for Business and Trade spokesman said: "This Government believes that steel plays a vital role in the UK economy, supporting local jobs and economic growth.
"We introduced the British Industry Supercharger to make our steel industry more competitive by bringing down energy prices and we protecting the UK steel industry from unfair trading practices.
"We are working closely with the sector to secure a sustainable, decarbonised and competitive future for steel."
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