Bulgaria’s anti-monopoly watchdog has rejected a demand by Ukrainian arms company Ukrinmash to stop the Balkan country’s 81.3 million levs ($50.2 million) fighter jet deal with Russian Aircraft Corporation MiG.

Bulgaria last month asked the Russian company to overhaul and maintain 15 of its ageing MiG fighter jets. The country was about to sign a four-year deal, but had to put that on hold following an appeal by Ukrinmash.

The decision of the Commission for the Protection of Competition can be appealed within three days of notification, the watchdog said in a statement.

Bulgaria considered the MiG maker as the only company capable of providing reliable support for the aircraft and did not invite other bidders for the deal.