CARACAS, Venezuela (AP) — An Iran-flagged supertanker carrying more than 2 million barrels of condensate has docked at a Venezuelan port, according to an independent oil tanker tracking firm.

It is the first condensate shipment of the year from Iran to arrive in Venezuela as part of a relationship between the two oil-exporting nations that are under U.S. economic sanctions. The Starla docked Monday in a seaport in northeastern Venezuela.

Samir Madani, co-founder of TankerTrackers.com, said the ship is carrying 2.1 million barrels of a very light form of oil based on natural gas that Venezuela’s state-owned company uses to dilute its heavy crude oil to turn into an exportable blend.

Madani said the vessel departed Iran on Dec. 11 and turned off its mandatory automated identification system for more than a month and a half. The system is used to prevent collisions, but companies in recent years have adopted a number of techniques, including turning it off, to evade detection as the U.S. has expanded economic sanctions.

Iran maintains close ties to Venezuelan President Nicolas Maduro and has shipped gasoline and other products to the country amid a U.S. sanctions campaign.

Madani said vessels carried condensate from Iran to Venezuela four other times since 2020, bringing in more than 8.3 million barrels. He added that a tanker with 620,000 barrels from the Middle East, presumably Iran, also docked in the South American country.