Commercial air transportation can only be performed by Montenegrin air carriers majority-owned by Montenegro and/or its citizens and under their effective control, unless otherwise determined by the concluded international agreements. Pursuant to the Law on Air Traffic, ECAA air carriers (which include those from EU/EEA Member States and other Western Balkans countries) may perform cabotage on the territory of Montenegro and international scheduled flights in accordance with the ECAA agreement subject to notification of their intended flights, while other foreign air carriers may only engage in such commercial air transportation activities subject to an authorisation by the Montenegro Civil Aviation Agency in accordance with concluded international agreements. As per the OECD FDIRRI methodology, the preferential treatment accorded to ECAA air carriers or other any other partner country as per commitments under international agreements is not taken into account. Per the FDIRRI methodology, which draws on the OECD's Code of Liberalisation on Capital Movements rules, only preferential treatment arising from EU/EEA membership is admitted to be reflected in the FDIRRI. 
"Article 4
Certain terms used in this law have the following meanings: [...]
12) The ECAA Agreement is a multilateral agreement between the European Community and its member states and the Republic of Albania, Bosnia and Herzegovina, the Republic of Bulgaria, the Republic of Croatia, the Former Yugoslav Republic of Macedonia, the Republic of Iceland, the Republic of Montenegro, the Kingdom of Norway, Romania, the Republic of Serbia and the United Nations Interim Administration Mission in Kosovo on the establishment of a common European aviation area;
13) effective control is a relationship established by rights, contracts or other means that, separately or jointly, taking into account the relevant facts or laws, give the possibility to exercise direct or indirect influence on a legal or physical person, especially through the right to use the entire property or part of the property of a legal or physical person persons or rights or contracts that provide a decisive influence on the composition, voting or decisions of the bodies of a legal entity or in some other way provide a decisive influence on the conduct of business of a legal or natural person;
[...]
Authorization to fly in Montenegrin airspace for foreign aircraft
Article 16
(1) Foreign aircraft may fly in Montenegrin airspace only on the basis of approval, unless otherwise determined by a confirmed international agreement.
(2) Air carriers that are prohibited from flying in the territory of the European Union and are on the European Union's list of prohibited air carriers cannot fly in Montenegrin airspace.
(3) The approval from paragraph 1 of this article is issued for:
  1) foreign state aircraft, the state administration body responsible for foreign affairs, with the consent of the state administration body responsible for defense affairs;
  2) foreign civil aircraft, Agency.
(4) The approval from paragraph 1 of this article can be:
  1) permission to enter (flying);
  2) approval for regular or occasional transportation.
(5) The Agency's approval is not required for flights performed in accordance with the ECAA Agreement, provided that the air carriers provide the Agency with notification of the intended flight.
(6) The list of the European Union referred to in paragraph 2 of this article is published on the Agency's website.
(7) The conditions and manner of issuing the approval referred to in paragraph 1 of this Article shall be prescribed by the Ministry, with the consent of the state administration authorities responsible for defense and foreign affairs.
[...]
Conditions for performing transportation and other commercial services in air traffic
Article 23
(1) Commercial air transportation may be performed by a legal or natural person that has an operating license and an air operator's certificate (hereinafter: AOC) issued by the Agency, in accordance with this law.
(2) Other commercial services other than the transportation of persons and things (including the provision of air services) may be performed by a legal or natural person or a state administration body that has an AOC, in accordance with this law.
Conditions for issuing an operating license
Article 24
(1) An operating license is issued at the request of a legal or natural person, provided that:
  1) is registered in the Central Register of Business Entities (hereinafter: CRPS) for the performance of air transport services or in combination with other commercial aircraft services or aircraft repair and maintenance;
  2) has its headquarters in Montenegro;
  3) has an AOC;
  4) has one or more aircraft in his possession or on the basis of a dry lease agreement;
  5) has an appropriate organizational structure that enables the Agency to verify the fulfillment of prescribed conditions;
  6) is majority owned by Montenegro and/or its citizens and under their effective control, unless otherwise determined by the concluded international agreement;
  [...]
Unauthorized advertising and offering of services
Article 33
Commercial air transportation and other commercial services referred to in Article 23 of this law may be advertised and offered only by a legal or physical entity that is registered to perform these activities and that has an operating license and/or AOC.
International scheduled air transport and cabotage
Article 34
(1) International scheduled air transportation may be performed by a Montenegrin air carrier that, in addition to the requirements from Article 23 paragraph 1 of this law, meets the conditions stipulated by international agreements and other international acts that regulate the safe and regular performance of international scheduled air transportation.
(2) A foreign air carrier may perform international scheduled air transport with Montenegro, in accordance with:
  1) ECAA agreement;
  2) concluded international agreements or
  3) conditions from the approval for carrying out transportation.
(3) A foreign air carrier may perform cabotage on the territory of Montenegro in accordance with the ECAA agreement.
(4) The Agency may authorize a foreign air carrier to perform air transportation between places within the territory of Montenegro (cabotage) in accordance with concluded international agreements.
Establishment of scheduled air transport
Article 35
The Montenegrin air carrier can perform scheduled air transportation within Montenegro without the approval of the Agency, and scheduled air transportation in international air traffic is established in accordance with concluded international agreements.[...]" (Law on Air Traffic, OG MNE No. 30/2012 of 06/08/2012, as amended [google translation])

Law on Air Traffic, OG MNE No. 30/2012 of 06/08/2012, as amended [google translation]
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