Reform UK's leader Nigel Farage has said his party wants to bring blast furnaces back to Port Talbot should it come to power.
During a visit to the town, Farage said his party wanted to see Wales "reindustrialise to prosper and grow", and would allow coal to be mined in the country for use in the steelworks.
But he admitted it would not be "easy" to reintroduce the furnaces, which he said would cost billions.
An industry source told BBC Wales that the two furnaces that closed last year cannot be reused, with the structures containing hundreds of tonnes of solidified molten iron.
After he initially talked about reopening Port Talbot's furnaces at a press conference, Farage later said it would be "impossible" for the old structures to be reopened.
Labour First Minister Eluned Morgan said the policy was "absolute nonsense" and she wasn't sure "if people in Wales want to see their grandchildren going back down the pits".
Rivals in the Conservatives and Plaid Cymru said Farage was offering "empty" promises and policies.
Traditional steelmaking ended in Port Talbot last year as part of a plan to eventually move to greener electric arc, using scrap steel rather than iron ore.
Its operator Tata said it had been losing £1m a day. The site had two furnaces.
Challenged on how his ideas would be achieved if he won a Senedd election, Farage said it was an "ambition" the party has which would need UK government support.
