EU chief Ursula von der Leyen described the developments as “greatly concerning”, as the 27-nation bloc moved to withdraw non-essential personnel from the region.

“Ensuring nuclear safety and preventing any actions that could further escalate tensions or undermine the global non-proliferation regime is of critical importance,” said von der Leyen, the European Commission president.

“We call on all parties to exercise maximum restraint, to protect civilians, and to fully respect international law,” she added in a joint statement with European Council president Antonio Costa.

The US and Israel launched a wave of strikes against targets in Iran today, triggering explosions in the capital Tehran, with Israel’s public broadcaster reporting that supreme leader Ayatollah Ali Khamenei had been targeted.

The Islamic republic retaliated with barrages of missiles at Gulf states and Israel.

Explosions were heard in the capitals of Saudi Arabia, Bahrain, Qatar and the UAE – all countries that host US forces.

Blasts were also reported in the skies over Jerusalem after the Israeli military said a “barrage of missiles was launched” towards the country.

“Our consular network is fully engaged in facilitating departures for EU citizens. Non-essential EU personnel are being withdrawn from the region,” said the EU’s top diplomat, Kaja Kallas.

The EU’s Aspides naval mission in the Red Sea remained “on high alert” and stood ready to help keep the maritime corridor open, Kallas said, adding she had spoken to Israeli foreign minister Gideon Saar and “other ministers in the region”.

“The latest developments across the Middle East are perilous. Iran’s regime has killed thousands.

“Its ballistic missile and nuclear programmes, along with support for terror groups, pose a serious threat to global security,” she wrote on social media.