Unions have warned of a bitter fight ahead after their plans to avert thousands of job losses at Tata Steel were rejected by the company.

Tata had announced in January a consultation on cutting up to 2,800 jobs in the UK, the majority of them at the country’s biggest steelworks in Port Talbot, South Wales.

It followed confirmation that the Indian-owned firm wanted to close down the blast furnaces at the plant and replace them with electric arc furnaces under a plan to reduce emissions and costs.

GMB, Unite and Community union representatives met Tata counterparts at a London hotel to discuss the way forward on Thursday morning.

But the GMB said Tata informed them that the blast furnaces would be closed by the end of September, describing the decision as an “unwelcome but not expected slap in the face”.

The company has consistently argued that its £1.25bn investment would secure the future of UK steelmaking.

“It would protect the majority of jobs, reduce the UK’s carbon emissions by five million tonnes a year and could kickstart a green industrial revolution in South Wales,” a spokesperson said.

However, its operations are now widely expected to face strike action.

Members of Community and the GMB are being balloted on whether to walk out over the plans.

Unite members have already voted in favour of industrial action.