Operating licences for air operators may only be granted to undertakings majority owned and effectively controlled by EU states and/or nationals of EU states.
"Article 4 - Conditions for granting an operating licence:
An undertaking shall be granted an operating licence by the competent licensing authority of a Member State provided that:
[...]
(f) Member States and/or nationals of Member States own more than 50 % of the undertaking and effectively control it, whether directly or indirectly through one or more intermediate undertakings, except as provided for in an agreement with a third country to which the Community is a party; [...]"
(Regulation (EC) No 1008/2008 on common rules for the operation of air services in the Community, Article 4(f))

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"§ 40.  Operating licence:
 (1) The operating licence of the air operator specified in Regulation (EC) No 1008/2008 of the European Parliament and of the Council on common rules for the operation of air services in the Community (OJ L 293, 31.10.2008, pp. 3–20) will be issued by the minister responsible for the field.

 (2) The procedure for the issue, suspension and revocation of operating licences will be established by the Government of the Republic.
[...]"
(Aviation Act (RT I 1999, 26, 376; last amended 25.11.2020), §40 [unofficial translation])
Regulation (EC) No 1008/2008 on common rules for the operation of air services in the Community, Article 4(f)
Aviation Act (RT I 1999, 26, 376; last amended 25.11.2020), §40
[<a href="https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A02008R1008-20201218 ">Regulation</a>],[<a href="https://www.riigiteataja.ee/en/eli/ee/517122020009/consolide/current">Act</a>]