Only ships and vessels with Lithuanian state flag and registered in Lithuania or any European Union member state flag are allowed to provide maritime waterway cabotage services. Registration in the Lithuanian Ship Register requires that the owner of the ship is a citizen of the Republic of Lithuania or a legal person registered in the Republic of Lithuania.
"Article 3 . Right to provide maritime cabotage services:
To provide maritime cabotage services as defined in December 7 Council Regulation (EEC) No Regulation (EEC) No 3577/92 applying the principle of freedom to provide services to maritime transport within Member States (maritime cabotage) may apply in the Republic of Lithuania to vessels flying the flag of the State of Lithuania and to vessels granted such a right by this Regulation.

Article 7 . Ship's flag:
1 . The right to fly the flag of the State of Lithuania is granted to ships registered in the Register of Seagoing Ships of the Republic of Lithuania.
[...]

Article 8 . Ship registration:
1 . A ship shall be registered in the Register of Seagoing Ships of the Republic of Lithuania if it is designed and built for navigation at sea and has documents confirming this, and the owner of the ship is a citizen of the Republic of Lithuania or a legal person registered in the Republic of Lithuania.
[...]"
(Law on Merchant Shipping (12 September 1996, No.I-1513; last amended 19 December 2019), Articles 3, 7 and 8 [google translation])
Law on Merchant Shipping (12 September 1996, No.I-1513), Articles 3, 7 and 8
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