When the entire global market is dominated by a totalitarian statewith the avowed aim of destroying western industry using forced cheap labour to produce a steel surplus, this is inevitable. This is how China does business.
I don't have a clue how you could prevent it.
Some degree of protectionism I guess- state driven infrastructure projects that a) need a lot of steel and b) said steel can only be purchased in the UK. You could come up with a carbon cost requirement for the steel that would rule out any that came from outside the UK's borders.
When the entire global market is dominated by a totalitarian statewith the avowed aim of destroying western industry using forced cheap labour to produce a steel surplus, this is inevitable. This is how China does business.
I don't have a clue how you could prevent it.