Starmer is talking about the new Type 31 and Type 26 frigates, most of which are already under construction. Only 3 ships are at a point where you could change the order, which amounts to - at best - about 15k tonnes of steel. That's a nice order - but the UK steel industry produces about 9m tonnes a year. 15k tonnes doesn't make much of a difference. It's almost perfect Starmer: sounds great to the Daily Mail, makes zero difference to working people.

https://www.mirror.co.uk/news/politics/british-steel-used-make-warships-30852874