Iran is warning that it will respond after a Ukrainian strike on an Iranian commercial vessel in the Caspian Sea left one sailor dead and another wounded, with Foreign Minister Abbas Araqchi declaring that the attack “cannot go unanswered.”

According to Iranian officials, the strike caused an explosion aboard the vessel, killing one crew member and injuring another.

Araqchi delivered the warning during separate telephone conversations with European Union foreign policy chief Kaja Kallas and Russian Foreign Minister Sergei Lavrov, later disclosing the discussions in a post on X.

In a statement released by Russia’s Foreign Ministry, Lavrov expressed his condolences over the death of the Iranian sailor during the attack.

The Russian statement said Araqchi thanked officials in Russia’s Astrakhan region, where the ship had begun its voyage, for assisting the crew following the incident. It added that the Iranian foreign minister “and stressed the need to put an end to such adventures by the Kyiv regime.”

The Kremlin also said Araqchi briefed Lavrov on Iran’s ongoing diplomatic initiatives, informing him of “continuing diplomatic efforts aimed at de-escalating tension in the Middle East.”