American Airlines (AA, Dallas/Fort Worth) says it has been forced to write-off over half a billion dollars in revenue it has been unable to repatriate from Venezuela following difficulties in converting local bolivars into US dollars.

In an SEC filing, the carrier said it would recognize a USD592 million special charge in the fourth quarter of 2015 to write off all of the value of Venezuelan bolivars held.

American is one of several foreign carriers to have been seriously affected by the Venezuelan government's unwillingness to cooperate in the repatriation of hard-currency equivalents of local ticket sales.

IATA's latest figures show that international airlines are now owed USD3.7 billion in revenue most of which dates back to 2013.

For its part, petroleum-dependent Venezuela is struggling to balance its own books following the dramatic fall in the price of oil over the past 18 months. In the wake of the routing of the Venezuelan Socialist Party (Partido Socialista Unido de Venezuela - PSUV) in December's polls, president Nicolas Maduro has now invoked the power to rule-by-decree in a bid to by-pass a parliament dominated by the opposition.

Maduro blames Venezuela's ills on an international conspiracy fronted by private business and backed by 'imperialist' foreign countries - the United States in particular.