Malaysia Airlines has launched MHupgrade, a new auction system allowing passengers to bid for a seat upgrade.
Passengers who have booked an economy or business class ticket will receive an email informing them of available seats in the next class up.
They then decide if they want to bid for an upgrade and, if so, enter the highest amount they are prepared to spend.
Successful bidders will enjoy all the benefits of the higher class, including priority check-in, baggage allowance, boarding and in-flight meals, plus lounge access.
Only successful bids will be charged and passengers will be informed 48 hours prior to departure.
Dr Hugh Dunleavy, Malaysia Airlines' director of commercial, said: "This is a great opportunity for guests to get an upgrade to a premium cabin class.
"Make us an offer and we will only charge once your bidding is successful. There will be no introductory cost and unsuccessful upgrades will not be charged.
"On your upgraded sector, you will be able to enjoy the benefits of your upgraded class which includes priority check-in, baggage allowance, boarding and in-flight meals of business or first class as well as access to Malaysia Airlines' lounges or other airline partners' lounges worldwide."