In the face of U.S. pressure, Greece has said it will not assist an Iranian supertanker sought by Washington after it was released by Gibraltar and is now believed to be heading to a Greek port.

Deputy Foreign Minister Miltiadis Varvitsiotis on August 21 told Greek TV that Athens had 'faced pressure' over the vessel that Washington claims is linked to Iran's Islamic Revolutionary Guards Corps (IRGC), an organization sanctioned by the United States.

Varvitsiotis added that, in any case, the Adrian Darya 1, formerly known as Grace 1, was too large to enter any of Greece's ports and could not legally unload its $130 million worth of crude oil at European Union refineries.

Greek officials said a vessel of that size and draft would only be able to anchor at least 1 kilometer offshore at the ship's declared destination -- the southern port of Kalamata.

The Grace 1 was seized on July 4 by British Royal Marines off Gibraltar as it entered the Mediterranean Sea, suspected of transporting oil to Syria in violation of the bloc's sanctions.

It was allowed to leave the British territory on August 19 after giving local authorities assurances it would not travel on to Syria.

At the same time, Gibraltar rejected a warrant to seize the ship by the U.S. Justice Department, which alleged it had connections to the IRGC.

The United States on August 19 issued a warning to Greece, as well as to all ports in the Mediterranean Sea, about providing assistance to the Iranian tanker, Reuters reported, citing a U.S. State Department official.

Any aid would be interpreted as providing material support to the IRGC. Facilitating the tanker carries potential immigration and criminal consequences, the unidentified U.S. State Department official said.

Greece's deputy foreign minister said that, should the vessel enter Greek waters or anchor offshore, Athens will 'see' what it will do.

'We are sending a message that we are not prepared to facilitate the course of this ship to Syria,' Varvitsiotis said. 'And this is a message that we have made very clear.'

Varvitsiotis said Athens had not communicated with Tehran over the tanker.

'Nobody from the Iranian government has asked us for anything,' he said. 'In any case, I don't think the Iranian government is involved -- it's a commercial venture for which there may be some government support.'

Iranian Foreign Ministry spokesman Abbas Musavi said on August 19 that Tehran had warned the United States against seizing the tanker in open seas.

This and other shipping disputes have come amid rising tensions between Iran and the West, particularly the United States, and have included several incidents in and around the Persian Gulf, which sees around one-fifth of international oil shipments.

With reporting by AP, AFP, dpa, and Reuters

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