The industrial action at Port Talbot and Llanwern, Newport, will begin on 8 July and is expected to "severely impact" the company's UK operations, Unite said.

It comes in response to plans to close Tata Steel's blast furnaces in South Wales, putting 2,800 jobs at risk, according to the union.

Unite said it would be the first time in more than 40 years that steel workers in the UK have gone on strike.

Industrial action short of a walkout, including staff working to rule and a ban on overtime, began earlier this week.

The union's general secretary Sharon Graham said: "The strikes will go on until Tata halts its disastrous plans.

"Unite is backing Tata's workers to the hilt in their historic battle to save the Welsh steel industry and give it the bright future it deserves."

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