As a rule, maritime cabotage services are reserved for ships flying the Argentine flag and commanded by an Argentine captain. A foreign-flagged ship may be exceptionally granted authorisation to provide cabotage if Argentine ships are not available, in which case the foreign-flagged ship must be manned exclusively by Argentine personnel.
"ARTICLE 28.- The ships and naval artifacts that develop national cabotage navigation will be subject to the provisions of Decree Law 19,492 of July 25, 1944, ratified by Law 12,980 and modified by Law 26,778, as well as by the respective collective agreements current work.
ARTICLE 29.- Vessels and naval artifacts of foreign flag, which have been granted the Argentine flag treatment, must be manned exclusively by Argentine personnel, under penalty of loss of the benefits established in this law.
If the lack of availability of Argentine personnel is proven, foreign personnel may be authorized, in accordance with the provisions of article 112 of Law 20,094, modified by Law 22,228, giving preference to personnel from Mercosur member countries who prove their suitability. required, until Argentine personnel are available.
[...]
ARTICLE 30.- Vessels and naval artifacts of foreign flag that by virtue of Article 6 of Decree-Law 19,492 / 44, ratified by Law 12,980, are authorized to act in national cabotage for periods exceeding thirty (30) days consecutive or non-consecutive in the anniversary year, they must be manned exclusively by Argentine personnel, and may include foreign technicians as supernumeraries, in the manner and conditions established in this law. The aforementioned vessels, in addition to the provisions regarding personnel, must comply with the tax regulations established for Argentine flag vessels.
ARTICLE 31.- All ships and naval artifacts with the national flag or with Argentine flag treatment must be manned exclusively by Argentine or resident personnel, in accordance with the provisions of Articles 112, 142 and 143 of Law 20,094, remaining the adjustment contracts that are entered into within the framework of the respective collective bargaining agreements, under Argentine administrative and judicial jurisdiction.[...]" (Law No. 27.419 on the Development of the National Merchant Marine and Regional River Integration (28 December 2017), Articles 28, 29, 30 and 31 [google translation])
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"Article 1. - Navigation, communication and national cabotage trade will be practiced only by Argentine ships.
Art.2. - In order for an Argentine ship to be authorized to exercise commercial cabotage navigation and have the right to use the national flag in accordance with the legal provisions, it must meet the following conditions:
a) Be registered in the national registry;
b) Be commanded by Argentine captain and officers with Argentine title;
c) Be manned by Argentines in a minimum proportion of 25% of their role;
d) Compulsory use of the national language in the verbal and written command and service orders of the ship and in the annotations and books, and documents required by the Commercial Code (book III) and the inscriptions of the transmitters of orders, accommodation and compartments.
[...]
Art. 6. - When, due to exceptional circumstances, it is not possible to supply a coastal area with basic necessities or to fulfill a contract because Argentine ships are not in a condition to provide the corresponding service, the ministerial authority in which the national port authority acts is authorized, to grant precarious permission, in each case, to foreign ships to do so, and as long as those circumstances of force majeure persist, the same being empowered to regulate the procedure, as well as to delegate the aforementioned authorization to whoever it designates.[...]" (Decree-Law No. 19.492 on Navigation and National Cabotage Trade (25 July 1944), as amended by Law No. 27.445 of 18 June 2018, Articles 1, 2 and 6 [google translation])
Law No. 27.419 on the Development of the National Merchant Marine and Regional River Integration (28 December 2017), Articles 28, 29, 30 and 31
Decree-Law No. 19.492 on Navigation and National Cabotage Trade (25 July 1944), as amended by Law No. 27.445 of 18 June 2018, Articles 1, 2 and 6 
[<a href="http://servicios.infoleg.gob.ar/infolegInternet/verNorma.do?id=305213">Law</a>],[<a href="http://servicios.infoleg.gob.ar/infolegInternet/anexos/205000-209999/205303/texact.htm">Decree-Law</a>]