American Airlines Group Inc on Tuesday said it has written off more than half a billion dollars in revenue stuck in Venezuela because of currency controls. American, the world's largest airline, said in a regulatory filing it will recognise a $592 million special charge in the just-ended fourth quarter "due to continued lack of repatriations and deterioration of economic conditions in Venezuela."

The South American country's socialist government had compelled carriers to sell tickets in bolivars but made reconverting the sales into US dollars difficult. Globally, airlines have around $3.7 billion trapped in Venezuela as a result of its 12-year-old currency control system, the International Air Transport Association said in June.

Copyright Reuters, 2016