New Delhi: As Air India continues to look for new ways to boost revenues, the national carrier has now introduced a new bidding system to allow its passengers who booked economy tickets to upgrade to business class by paying an additional fare, chairman and managing director Pradeep Singh Kharola said.

"You have to bid for only the incremental amount. Whatever you have paid for the economy class ticket, you have paid… There is a cap we have put on the minimum bid one can make…People who have already booked tickets in economy class, we are giving them a chance to pay a little extra fare and come to the business class," Korola was quoted as saying.

Kharola added that the person who made the bid would get a refund if the upgrade is not successful. However, the airliner has no plans to open up its lounges to economy class passengers.

The bidding system, facilitated by American-based firm Optiontown, has already begun for flights to the United States, Europe, Australia, Japan and Hong Kong.

Air India started rationalising its costs for catering by carrying food stocked from India on its return journey to the country to cut back on catering costs on international flights, having recorded a 17 percent rise in passenger revenues during the April-December period of the fiscal year.