THE fallen Perth tycoon Pankaj Oswal has initiated court action challenging the appointment of receivers to Burrup Fertilisers while also suing the company he built for $US500 million ($460 million).

Mr Oswal is contesting the legality of ANZ Bank's decision to declare the company had defaulted and is seeking an injunction to prevent the receiver PPB Advisory selling his shares and assets in the business.

His wife, Radhika, began her own proceedings in February, claiming the events of the default that ANZ used to appoint receivers in December did not occur.

A court judgment last week revealed she owes the Tax Office $140 million and might have received $80 million in payments from Burrup Fertilisers.

Mr Oswal maintains ANZ acted illegally in appointing receivers.

''My position is and always has been that the events of default which ANZ alleges and relied upon to appoint the receiver did not and do not exist,'' Mr Oswal said in a statement announcing the court action yesterday.

Mr Oswal said he lodged documents in the Supreme Court of Victoria on Monday, the day it was reported Burrup Fertilisers had been put up for sale. Bids are understood to be due by May 30, which Mr Oswal said was proof the bank wanted to force a sale below market price.

''Given this ridiculously short period that international and local buyers have been given to consider a multibillion-dollar asset, conduct their due diligence and submit a bid, it seems clear that the process is designed to eliminate genuine competitive buyers and facilitate the purchase by Yara at below market value,'' he said in the statement. ''I reiterate my previous comments that I believe ANZ, PPB Advisory, and Yara [International, a company with a 35 per cent holding in Burrup] have colluded to force me to sell at a rock-bottom price.''

In joint court action, Mr Oswal is suing Burrup Fertilisers for $US500 million he claims he paid towards the construction costs of its liquid ammonia plant.

The Oswals left Australia after receivers were appointed in December and their assets, including a private jet, were later frozen.

The Commonwealth Bank also claims it is owed $US18 million by Garuda Aviation, which is associated with Burrup Holdings' majority shareholder Mr Oswal.