DUBAI (Bloomberg) -- Iran said an oil tanker that was seized by British forces near Gibraltar wasn’t destined for Syria.

The ship “was navigating in international waters,” Deputy Foreign Minister Abbas Araghchi said at a press conference in Tehran. He said the tanker wasn’t heading toward Syria, without saying where the vessel was going. “We consider this an act of piracy.”

Grace 1, a supertanker able to haul 2 MMbbl of crude, was arrested earlier this week on suspicion that it was going to breach European Union sanctions by delivering crude to Syria. The cargo came from Iran.

The Islamic Republic is consulting with the UK and Spain on the matter, Araghchi said.