The Government has been accused of "taking its eye" off industrial strategy as steelworkers wait anxiously for a decision on their future.
A crucial board meeting of steel giant Tata is being held in Mumbai, which could decide the fate of thousands of workers, especially at Port Talbot in South Wales.
Former business secretary Sir Vince Cable said: "Since the Conservatives have been in government alone they have taken their eye off the industrial strategy we set out in coalition.
"This risks undermining business confidence and investment. The Government must now seek to restore that confidence and work with Tata Steel to resolve this."
Tata announced over 1,000 job losses in January, including 750 at Port Talbot, but there are fears that more cuts could be made.
Roy Rickhuss, leader of the Community union, who has travelled to Mumbai for the meeting, said: "No-one underestimates the scale of the challenge we are facing but our steel industry is of vital importance to our communities, our families and our nation.
"Steel is the very foundation of our manufacturing base, even the Prime Minister has conceded that it would be simply unacceptable for Tata to end our steelmaking capacity."
Alan Coombs, chairman of the Port Talbot multi-union committee, who has any also travelled to Mumbai, said: "Our town was built on the steel industry.
"It has given us more than just jobs, it has shaped our lives and communities."
Steelworkers and companies have called for more action from the Government to tackle cheap Chinese steel imports and high energy costs which have been blamed for thousands of job cuts.
Unite national officer Harish Patel said: "These are deeply uncertain times for steelworkers and their communities.
"Independent analysis shows that Tata's own transformation plan will return the Port Talbot plant to a competitive footing, but it is clear that the UK government needs to play an active role in backing investment to secure the plant's future for generations to come.
"We would urge the UK government to take a more interventionist approach in securing the future of Port Talbot and steelmaking across the UK. The Scottish government did so last week and secured the future of two steel plants in Lanarkshire."
Unite Wales secretary Andy Richards said: "We urge the Tata board to show some steel and commit to steelmaking in Port Talbot and the UK for the long term. Port Talbot is an integral part of the Welsh economy, supporting jobs in the local community and throughout the manufacturing supply chain.
"Port Talbot's closure would devastate the Welsh economy. We urge the Tory government in Westminster to put aside political game playing and work with Unite and the Welsh Assembly government to save our steel."
The think tank IPPR said the issues facing the steel industry were part of a wider problem.
IPPR research found that Britain is under-performing across the foundation industries such as metals and chemicals.
Since 2000, the share of GDP contributed by such industries has shrunk by 43%, compared to an average decline across the OECD of 21%.
Shadow business secretary Angela Eagle said: "The steel industry is of vital strategic importance to the economy but it is hanging by the thinnest of threads.
"Against the backdrop of challenging global conditions for the steel sector, it is crucial that the government is prepared to act or we risk losing yet more high-skilled jobs and potentially an entire industry which is vital to our future prosperity."