MOSCOW -- Russia is closely following the developments regarding the Russian oil tanker "Marinera" tracked by the US military in international waters, where it is sailing lawfully, the Russian Foreign Ministry said on Tuesday.

According to the ministry, the Russian-flagged vessel has been tracked for several days by a US Coast Guard ship, despite being approximately 4,000 km away from the American coast.

The Russian side is closely following the developments with concern due to the abnormal attention being paid to the vessel by the United States, calling on Western countries that declare a commitment to freedom of navigation to "start implementing this principle with themselves," the ministry told Tass.

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"Marinera," formerly known as "Bella I," is subject to US sanctions, US media reported.

The tanker, scheduled to load oil in Venezuela, was unable to dock due to the US blockade. After being tracked by the US Coast Guard in December, the empty tanker painted the Russian flag on its hull, changed its name, and changed its country of registration to Russia.

At the end of December, Moscow sent a diplomatic note to Washington, demanding that it cease tracking the tanker.