Tehraninfo-icon:  Iraninfo-icon's Supreme Leader Ayatollah Seyyed Ali Khamenei Tuesday denounced, what he described as, Britaininfo-icon's illegal seizure of an Iranian oilinfo-icon tanker, warning that the act of "piracy" will not go unanswered.

Iran leader was reacting to the British military's seizure of oil tanker "Grace 1" off the coast of Gibraltar earlier this month on suspicion of carrying crude to Syriainfo-icon in breach of the European Unioninfo-icon's unilateral bans on the Arab state.

Reports, however, say the seizure took place at the behest of the United Statesinfo-icon, which has been bent on driving Iranian oil exports to "zero" as part of its sanctions against the Islamic Republic.

"The wicked Britain commits an act of maritime piracy and steals our ship," said Ayatollah Khameneiinfo-icon. "They (the British) perpetrate a crime and make it look legal."

"The Islamic Republic and faithful elements of the establishment will not leave this wickedness unanswered and will respond to it at an appropriate time and place," the Leader added. 

Ayatollah Khamenei further censured the Europeans' "arrogant" approach to a 2015 multilateral nuclear deal with Iran, whose fate is now hanging in the balance due to Europe's failure to meet its end of the bargain and compensate for the USinfo-icon's withdrawal.

"When it comes to the issues between us and the Europeans, the source of the lingering problems is their arrogance," the Leader added.

As stated by Foreign Minister Mohammad Javad Zarif, the leader said, the European signatories to the Iran deal -- the UKinfo-icon, Franceinfo-icon and Germanyinfo-icon -- have fulfilled none of the 11 commitments they have undertaken under the accord, with which Tehran had fully complied for an entire year.

Ayatollah Khamenei further referred to Tehran's recent decision to suspend the implementation of some of its commitments under the deal in reciprocation for Washington's exit last May and Europe's subsequent failure to fill in for the US.

"Now that we have begun reducing our commitments, they move forward," the Leader said. "You cheeky ones! You have not fulfilled your 11 commitments. [In response,] we have only begun reducing our commitments and this procedure will definitely go on."