As the previously detained Grace 1 tanker, since renamed the Adrian Darya 1, continues its voyage toward a port in southern Turkey, there's been a significant development regarding the 2.1 million barrels of Iranian crude aboard which the US has sought to capture, claiming the ship is engaged in illegal sanctions busting.

On Monday an Iranian government spokesman announced the 2.1 million barrels have been sold to an unnamed buyer while en route across the Mediterranean.

In statements made to reporters in Tehran, spokesman Ali Rabiei, said of the oil's as yet unmentioned unloading point, “The buyer of the oil decides where its destination is.” He added that the world is “witnessing the wrong policy by the U.S. in monitoring and intervention in others’ internal affairs.”

Image source: Getty/AFP

The Associated Press noted that "At market rates, the crude oil aboard the Adrian Darya would be worth about $130 million" and further that "anyone buying it likely would be targeted by U.S. financial sanctions."

Over the weekend the real-time ship tracking website MarineTraffic showed a change in the Iran-flagged Adrian Darya's destination. This after the US State Department threatened that should Greece provide any aid or facilities to the vessel carrying 2.1 million barrels of Iranian oil, it would be tantamount to "material support to terrorism".

The Unites States says the tanker is controlled by the Iranian Revolutionary Guards and thus deems any state's interaction with it support of a formally designated terrorist group. There's still an active US seizure warrant for the vessel.

The tanker's data initially had as its intended destination Kalamata, Greece, but later changed it during the voyage to Mersin, Turkey.

Tracking data now shows it plans to dock at the southern Turkish port on Aug. 31 — an interesting choice given Washington-Ankara relations are at a low point over Turkey's purchase of the Russian S-400 anti-air defense systems, and resulting cancellation of the US F-35 transfer.

Iran for its part has warned the US and UK not to interfere in the Iranian-flagged vessel's movement, even recently voicing the possibility of sending a military escort to ensure the ship's safe passage.