Nine top European airlines including Air France-KLM, British Airways and Deutsche Lufthansa are lobbying for a change in how aircraft sales are financed to allow them access to government export guarantees to make them more competitive.

The carriers from France, Germany, the UK and Spain want to rework an agreement between the US and the EU that limits benefits of government-backed export financing to certain airlines, according to the Wall Street Journal.

The home market rule created to boost overseas sales and help developing economies through loans or loan guarantees by a government to foreign buyers, forbids airlines from the Airbus and Boeing home countries from receiving the support.

British Airways chief executive Willie Walsh said that it clearly gave an advantage to those carriers that could access export credit.

The lobbying airlines believe that government guarantees give their rivals a boost of several million dollars an airplane.

The proposal by the nine airlines calls for opening export credits to all carriers worldwide, while limiting them to funding a maximum of 20% of their fleets with the guarantees.

The home market rule is an unofficial and non-binding agreement that was struck between the US and EU in 1986 to level the playing field between Boeing and Airbus.