IDF sets out legal justification for Khamenei strike

"As Commander-in-Chief, Khamenei was the final decision-maker on Iran’s military operations.

"During the ongoing conflict, he directed the use of force against Israel and oversaw the funding, arming, and coordination of the regime’s terror proxies, including Hezbollah, the Houthis, and Shiite militias operating across the region."

Shoshani added that, at the time of the strike, Khamenei "was with other senior Iranian military officials who also constituted lawful military targets".

He continued: "Under the principles of distinction, proportionality, and precautions, the strike complied with international law.

"Neutralising the regime’s Commander-in-Chief delivered a clear military advantage by degrading Iran’s ability to plan and coordinate attacks against Israel."

Latest reports suggest that Khamenei's son, Mojtaba, has been appointed to succeed him as supreme leader.

But the US, which is operating jointly with Israel, has pledged to assassinate any successor, with President Trump openly discussing the prospect of regime change as a war aim.

It comes after two of Iran’s most prominent religious leaders have issued a fatwa calling on Muslims worldwide to avenge Khamenei's death.

Hossein Noori Hamedani and Naser Makarem Shirazi, grand ayatollahs of the Islamic Republic, released a fatwa – a ruling made by Islamic legal scholars – against American and Israeli interests across the globe.

The pair ruled that “avenging the blood of the martyred leader of the revolution is obligatory for all Muslims,” adding: “Without doubt, criminal America and the bloodthirsty Zionists have reached the end of their path, and this time the powerful armed forces will deliver a decisive and unforgettable response.

"The people of Iran and the Islamic world are the avengers of the blood of the martyred leader of the Revolution.

"Seeking revenge is the religious duty of all Muslims worldwide so that the evil of these criminals may be removed from the world.”

The order has increased concern among analysts that Iran could plan terror attacks overseas in retaliation for Khamenei’s death.

Israel's National Security Council warned yesterday of potential attacks against Israelis and Jews abroad. In a statement, the council said it has identified “a surge in motivation and an increase in terrorist activity and threats” by the Iranian regime and affiliated groups to target Israelis and Jews worldwide.

Counter-terrorism expert Ghaffar Hussain told the Daily Mail: “Iran has a long history of exporting terrorism around the world and a track record of targeting dissidents and journalists in the UK.

"This is a very real threat that has been heightened since the outbreak of the war and one that the security services must remain vigilant to.”

And Avner Vilan, a former Israeli security official, added: “What concerns me more are smaller-scale actions - either individuals who take the fatwa as inspiration, or regime supporters in Europe who may interpret it as a religious order and take matters into their own hands.

'These may not necessarily be people directly working for Iran. They could be sympathisers or Shiite supporters of the regime who decide to act independently.

"What is more likely are sporadic acts carried out by individuals or very small groups. Even one person who believes they are following a religious order can cause havoc.”