Calls are growing from Iran's hard-liners for reciprocal action against the United Kingdom's seizure of an Iranian oil tanker. Last week, British marines off the coast of Gibraltar detained the supertanker — which was carrying 2 million barrels of crude to Syria — after it was found in breach of EU sanctions on exports of oil to the Syrian government.

The incident continues to draw the ire of Iranian authorities, who have called it an illegal move amounting to an act of "piracy." The Iranian Foreign Ministry has already grilled the UK ambassador in Tehran, expressing an official protest and demanding the immediate release of the vessel.

Foreign Minister Mohammad Javad Zarif, known for his intense Twitter diplomacy, lashed out at the decision by challenging it from a legal point of view. "Iran is neither a member of the EU nor subject to any European oil embargo," he wrote, suggesting that Tehran is not obliged to comply with EU sanctions on Syria. "Last I checked, [the] EU was against extraterritoriality," he tweeted in his characteristic wry tone. Zarif also warned that the act of "piracy" set a "dangerous precedent" and urged an immediate end to it.

That, however, did little to appease his relentless hard-line critics at home, who are rarely content with the moderate government's approach toward the West. The proper response to the "UK's insolence," according to ultraconservative Kayhan — which has close links to the office of Iran's supreme leader — should be sought in the form of "reciprocal action" rather than summoning the UK ambassador or posts on Twitter. Kayhan argued that a seizure of British tankers and vessels in the strategic Strait of Hormuz is the "legitimate right" reserved by the Islamic Republic: "The Iranian public expects a response in kind that would teach the UK a lesson … one that makes it regret the move." Kayhan did not elaborate on whether that "expectation" was based on an opinion poll.