Austrian aviation authorities have said ticketing for Aeroflot low-cost subsidiary Pobeda Airlines’ Moscow Vnukovo-Vienna Fly&Bus route “violates the bilateral arrangements based on the air transport agreement” between Russia and Austria, ATWonline reported.

An Austrian delegation raised concerns about the Fly&Bus service with Russian aviation authorities during negotiations at the end of July, details of which were published by Russia’s Federal Air Transport Agency at the beginning of September.

In December 2015, Pobeda launched daily Moscow Vnukovo-Bratislava (Slovakia) Boeing 737-800 service, the airline’s first international service. The route, which also includes bus service from Bratislava airport to the Vienna railroad station, is promoted by Pobeda as Moscow-Vienna services.

“The Austrian delegation stated that Pobeda Airlines shall bring its reservation and ticketing procedure into the compliance with its designation and rights. The Austrian delegation requested the Russian delegation to take steps to stop such operations which are not in compliance with the bilateral framework,” the document states.

Several years ago, Russia and Austria had a bilateral dispute concerning the ownership of Austrian Airlines. The Russian government argued that Austrian Airlines could not be considered a domestic carrier after it was acquired by Germany’s Lufthansa Group. According to most bilateral agreements, flights from any particular country to Russia could be operated by the carrier, owned and managed by residents of that country. The dispute was resolved and Austrian Airlines kept traffic rights for Russian routes.

Moscow Vnukovo-based Pobeda was launched in December 2014 and operates domestic and international flights. Pobeda’s fleet includes 12 Boeing 737-800s; the airline carried 1.99 million passengers in 1H 2016, up 80.7% year-over-year.