AMWU state secretary, Mr Jock Ferguson, said that steel specifications for the project favoured overseas companies.

Since the standards would be Japanese and not Australian, this put local firms at a complete disadvantage because steel would have to be imported, according to Mr Ferguson.

A Western Power spokesman rejected the claims and said the steel specifications were of an international standard, which would not be too difficult to meet for local firms. The spokesman added the low value of the Aussie dollar would make local firms more competitive.