The ongoing investigation into anti-competitive practices by some of the world's best-known carriers has nervous airline executives trying hard to estimate any potential fines.

Qantas chief executive officer Geoff Dixon said today that Qantas would make a provision of US$40 million to cover a potential fine that may be imposed in the USA as a result of conduct undertaken by Qantas' freight division.

Dixon obviously believes any sanction against the Australian carrier would be considerably less than the fines handed down on British Airways and Korean Air. On August 1, BA and Korean were fined hundreds of millions of dollars for collusion and price fixing.

Qantas has been cooperating with regulators in the US, Europe, Australia, New Zealand and other jurisdictions in their investigation into alleged price fixing in the air cargo market.

These investigations revealed that the practice adopted by Qantas Freight and the cargo industry generally to fix and impose fuel surcharges was likely to have breached relevant competition laws.

However, Qantas said it had not been possible to quantify any direct or indirect liability associated with these matters.

This was a line also taken by Cathay Pacific chairman Christopher Pratt who last week said the airline was cooperating with authorities on the anti-trust investigation.

Pratt said: "Given the uncertainties surrounding these issues, no reliable estimate of any potential liability can be made at this time by Cathay Pacific."

The US Department of Justice announced that BA and Korean had agreed to plead guilty and pay separate $300 million criminal fines for their roles in conspiracies to fix prices of passenger and cargo flights. British Airways subsequently announced that $200 million of its fine related to cargo.

"Based on these developments, a decision has been made to make a $40 million provision in the 2006/07 financial accounts," Dixon said.

But the real fear for those airlines found guilty is the prospect of class action suits by disgruntled shippers. Although difficult to prove, the loss of such a court challenge could prove financially devastating.

"At this stage, it is too early to make a reliable estimate of possible fines in other jurisdictions or of possible liability to third parties under class actions," Dixon said. "We expect these amounts will be known over the next two years."

The Qantas CEO said the carrier had strict policies requiring compliance at all times with all laws governing its Australian and international operations.

"We have investigated this issue thoroughly and are confident that the unacceptable conduct was limited to a small number of people," he said.

Dixon said that as the matter was before the regulators, it was not appropriate for Qantas to comment further at this stage.