Qantas has been forced to pay AU$20 million in fines after being caught in a price fixing cartel with British Airways.

The Australian Competition and Consumer Commission (ACCC) says between 2002 and 2006, Qantas and British Airways fixed prices on fuel surcharges on international air freight.

ACCC chairman Graeme Samuel says that amounts to price fixing, but he says knowledge of the conduct did not extend beyond the freight division.

"It is not alleged that it got up to the levels of the board or the chief executive, it was much more of a local matter," he said.

The regulator says both airlines have voluntarily made admissions in relation to the conduct.

The ACCC launched proceedings against the two airlines in the Federal Court, and Qantas has entered into a deed of settlement to pay a penalty of AU$20 million.

Qantas chief executive, Geoff Dixon, says the airline was made aware of the allegations in 2006, and apologises unreservedly for the conduct of the employees involved.

Qantas has already paid millions of dollars in fines to US authorities after being prosecuted over international air cargo price fixing.

The ACCC is hoping to take further action against other airlines involved.

In July a former senior Qantas executive, Bruce McCaffrey, was sentenced to six months in a US jail for his role in international air cargo price fixing.

Lawyers involved in a class action against Qantas over the price fixing say they will be seeking hundreds of millions of dollars in damages.

Lawyer Kim Parker from Maurice Blackburn, says that is the amount estimated to have been lost by hundreds of businesses using Qantas international air freight service.

"Because it involves a cartel that extended over an eight-year period at least, and it involved a very large market in Australia which is international air freight, being geographically remote from the rest of the world, it means the damages claim in this case are very significant," he said.