Mining billionaire Andrew Forrest has defended attempts by his company, Fortescue Metals Group, to defer more than $200 million in royalty payments to the Western Australian Government, saying the failed attempt was based on "sound logic".

In an interview on ABC radio, Mr Forrest also said his High Court challenge against the federal government’s mining tax was about conquering evil. All it took for evil to win was for good people to do nothing, the Fortescue chairman said.

Shedding wealth ... mining baron Andrew Forrest. Credit:Rob Homer

‘‘We’ve decided not to do nothing,’’ he said. Fortescue is challenging the legality of the minerals resource rent tax (MRRT), levied against iron ore and coal miners’ super profits. The 30 per cent tax took effect from July 1.

‘‘Our enthusiasm to run this case is because we believe it’s fundamentally unconstitutional,’’ Mr Forrest said, adding that the tax interfered with the rights of states.