The European Union on Wednesday condemned an airstrike on the Iranian embassy in Damascus on April 1 that killed seven people and called on countries in the region to show restraint, Reuters reported.

Iran holds Israel responsible for the attack, which killed two of its generals and five military advisers at its embassy compound in Damascus.

"In this highly tense regional situation, it is imperative to show utmost restraint," Peter Stano, a spokesperson for the executive European Commission, said in a post on X.

"The principle of the inviolability of diplomatic and consular premises and personnel must be respected in all cases and in all circumstances in accordance with international law."

Speaking to Al Jazeera TV while visiting the Middle East, Spanish Prime Minister Pedro Sanchez said the "unacceptable" attack risked stoking an escalation of the conflict in the region and urged Israel to explain if it played any role.

"It's not acceptable, it needs to be clarified by the Israeli government... We are very concerned about the situation and that is why we ask the Israeli government to try to avoid this regional escalation," Sanchez said.

Iranian Leader Ayatollah Ali Khamenei vowed revenge for Monday's airstrike, which destroyed a consular building adjacent to the main embassy complex in the upscale Mezzeh district of the Syrian capital.