United Nations, Feb 28 : As the United Nations Security Council prepared for an emergency session on Saturday, Secretary-General Antonio Guterres condemned what he called the "military escalation in the Middle East".

He said the US-Israel use of force against Iran and Tehran's retaliation across the region "undermine international peace and security".

France's President Emmanuel Macron, who said the US-Israel attack on Iran has "grave consequences for international peace and security", called for the urgent meeting of the Council on Iran.

Iran's Foreign Minister Abbas Araghchi wrote to the Council asking for its intervention, saying the US and Israel had violated international law.

Two officials of UN agencies also expressed their concern over the developments in the Middle East.

UN Human Rights High Commissioner Volker Turk said, "I deplore the military strikes across Iran this morning by Israel and the United States of America, and the subsequent retaliatory strikes by Iran."

World Health Organisation Director-General Tedros Adhanom Ghebreyesus said, "I am deeply troubled by the situation unfolding today across the Middle East. My heart goes out to the civilians trapped in the crossfire."

Both of them joined UN Chief Guterres in calling for an immediate end to the conflict.

Guterres said, "I call for an immediate cessation of hostilities and de-escalation. Failing to do so risks a wider regional conflict with grave consequences for civilians and regional stability. I strongly encourage all parties to return immediately to the negotiating table."

The US-Israel attack followed negotiations between the US and Iran with Oman as the mediator that apparently did not make headway.

US President Donald Trump said on Friday that he was not happy with the talks.

"I'm not happy with the fact that they're not willing to give us what we have to have," he said about a sticking point -- the demand that Iran completely stop enriching uranium.

Oman's Foreign Minister Badr bin Hamad Al Busaidi, who was in interlocutor in the negotiations, and had said on Friday that there was progress, deplored the attack on Saturday.

He said on X, "Active and serious negotiations have yet again been undermined."

"I urge the United States not to get sucked in further," he added.

Trump explicitly came out for a regime change in Iran after his military, joined by Israel, pummeled targets across Iran, aiming to decapitate the country's politico-religious and military leaderships.

Iran retaliated with missile attacks on Israel and on targets in the United Arab Emirates, Qatar, Bahrain, Kuwait and Saudi Arabia, as well as on US forces at sea in the region.

Aragachi in his letter to the UN Security Council warned, "All bases, facilities and assets of the hostile forces in the region shall be regarded as legitimate military objectives within the framework of Iran's lawful exercise of self-defence."

Guterres in his statement said, "All Member States must respect their obligations under international law, including the Charter of the United Nations."

"The Charter," he said, "clearly prohibits 'the threat of the use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations'."

/IANS