Iran’s Supreme Leader, Ayatollah Ali Khamenei, has vowed that the country’s armed forces will deliver a forceful response to Israel’s large-scale aerial assault, which struck multiple sites across Iran early on June 13.

In a televised address on June 14, Khamenei declared, “The armed forces will act with full strength. The vile Zionist regime will be left helpless and will not escape unscathed. The Iranian nation can be assured there will be no leniency.”

The speech marked Khamenei’s first public statement since the attack, which killed top military officials, including IRGC commander Hossein Salami and armed forces chief Mohammad Bagheri. Several nuclear scientists, including Mohammad Mehdi Tehranchi and Fereydoon Abbasi, were also reported dead.

Iranian state military media claimed that during air defence engagements on June 13, several incoming munitions, drones, and small UAVs were intercepted, and “in a successful operation, an Israeli fighter jet was hit.”

The Supreme Leader’s remarks come as Iran’s political and military leadership reiterated their legal right to retaliate under Article 51 of the UN Charter.

Deputy Foreign Minister Abbas Araghchi said Israel's action constituted an “illegal act of aggression,” adding that the US would also be held responsible due to its backing of Israel.

Tensions remain high in Tehran and other cities, with reports of explosions and air defence activity in Qom, Tabriz, Hamedan, Isfahan and Buin Zahra. Local authorities confirmed missile intercepts, but the scale and nature of Iran’s response remained unclear.

Israeli Prime Minister Benjamin Netanyahu claimed the strikes targeted military and nuclear assets and called the operation a “decisive moment.” Washington denied involvement and said its priority remains protecting US troops in the region.

With both sides signalling readiness for escalation, the next phase of the confrontation could determine the broader trajectory of conflict dynamics across the Middle East.