British Airways has been fined almost £3m after pleading guilty to taking part in a cartel that fixed prices on air cargo in Canada, reports the Financial Times.

The carrier was fined £121.5m in July 2007 for a separate price-fixing cartel with Virgin Atlantic involving surcharges on passenger fares.

The fine by Canada’s competition bureau is the latest in a series of penalties imposed by authorities on airlines around the world in what has become one of the biggest international cartel investigations.

Canada’s competition bureau announced that BA had “admitted to fixing surcharges on the sale and supply of international air cargo exported on certain routes from Canada between April 2002 and February 2006”.

Competition authorities in the US, EU and Australia have been investigating price-fixing in the air freight industry. US investigations have led to the prosecution of 15 airlines and resulted in fines of more than $1.6bn.

The news comes at the same time as BA faces the possibility of Christmas strikes and prepares to announce record losses on Friday when it presents its second-quarter results.

The airline made a record £401m ($659m) pre-tax loss last year, and has been warning that it could suffer an even bigger full-year loss this year.

Speaking at the launch of its first direct Heathrow to Las Vegas flight on Monday last week, chief executive Willie Walsh said: “I get no comfort from the fact that I am running a business that is going to report a loss two years in a row.”

Walsh also reaffirmed his committment to carry out controversial staff restructuring to try and secure the long-term survival of the airline.

His plans, which involve 1,800 redundancies, removing a member of crew on long-haul flights and turning a number of full-time positions into part-time roles has been met with strong opposition from cabin crew.

They will meet at Sandown Park racecourse later today to discuss the airline’s plans to change their working conditions and the union will announce the results of the strike ballot on December 14 – which could mean strikes by Christmas.

The union said it had started proceedings at the High Court in London for an injunction against BA imposing new pay and conditions on workers from November 16.

“BA is changing people’s contracts and they are doing it in a unilateral way,” Unite said.