Australia's largest coal hauler and transporter QR National stabilised at $2.55 per share at its mid-day introductory debut at the Australian stock exchange and so far raised some $4.6 billion for the Queensland government.

This would be Australia's biggest float since the third tranche of Telstra shares was sold by the Howard administration in November 2006.

London-based hedge fund - the Children's Investment Fund Management - has emerged as the second-biggest shareholder in QR National with a 6.1 per cent stake. While the third largest is Colonial First State Investments with a 5.1 per cent stake.

The Queensland government, which will retain a 34 percent stake in QR National until August 2012, had so far raised $4.6 billion from the initial public offering, which it plans to use to help repay debt and regain its AAA investment-grade credit rating.

QR National remains Australia's biggest coal hauler and transporter in terms of tonnage moved and delivered to key Asian countries led by China and Japan.

QR National claims that the IPO is a safe way of engaging into the Asian economic success.

The controversial sale attracted criticisms from various sectors while the uncertain financial environment prompted pessimistic projections from investors following the dismal result of the recent Myer float.

Such scenarios, however, failed to dampen the upbeat outlook of the Queensland government on the QR National privatisation effort as State Treasurer Andrew Fraser asserted that the public float would be largely supported by resources demand coming from China and India.

In launching the Brisbane IPO on Tuesday, Mr Fraser stressed that the float's core strength lies on the insatiable demand by both China and India for Australian resources, underscoring that "if you believe in the growth story of Asia, you can believe in this stock. It is a very durable investment."