The United Nations Security Council held an emergency meeting on Saturday afternoon following US and Israeli military strikes against Iran, amid escalating tensions across the Middle East.

The meeting was convened at the request of China, Russia, France, Bahrain and Colombia.

China's permanent representative to the UN, Fu Cong, said it was "shocking" that the military strikes occurred at a time when diplomatic negotiations between the United States and Iran were ongoing, urging relevant parties to demonstrate political sincerity and resume talks as soon as possible.

China is "deeply concerned" about the escalation of tensions in the region, Fu said, noting that US and Israeli military strikes against Iran have triggered a "sudden escalation of regional tensions". He urged all parties to abide by the purposes and principles of the UN Charter.

"China has consistently maintained that all parties should observe the purposes and principles of the UN Charter, and opposes and condemns the use or threat of force in international relations," he said.

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The United States and Israel on Saturday launched "major combat operations" against Iran. Iran later retaliated with counterattacks targeting Israeli and US military installations in several Arab states across the region. As of Saturday, Iran had launched strikes toward Qatar, Bahrain, Kuwait, Iraq, the United Arab Emirates, Jordan, Saudi Arabia, Syria and Lebanon.

Fu stressed that the sovereignty, security and territorial integrity of Iran and other countries in the region must be respected, adding that China is "deeply saddened" by the heavy civilian casualties caused by the conflict.

"At no time should the red line of protecting civilians in armed conflict be crossed, and the indiscriminate use of force is unacceptable," he said, calling on all parties to fulfill their obligations under international law, including international humanitarian law, and to effectively protect civilians and avoid attacks on civilian facilities.

"Force is not the right way to resolve international disputes," Fu said. "The spillover of escalating tensions in the Middle East serves no one's interest. Resolving differences through dialogue and negotiations is the only viable way forward."

UN Secretary-General Antonio Guterres also condemned the US-Israeli strikes and retaliatory attacks by Iran.

"We are witnessing a grave threat to international peace and security," he said, calling for the peaceful settlement of disputes and stressing that lasting peace can only be achieved through peaceful means, including genuine dialogue and negotiations.

The US and Israeli attacks occurred two days after the third round of indirect Iran–US nuclear talks mediated by Oman in Geneva, Switzerland. Technical discussions were scheduled to be held next week in Vienna. Guterres said he was "deeply regretful that this opportunity for diplomacy has been squandered."

"I strongly urge all parties to return immediately to the negotiating table, notably on the Iran nuclear programme," he said.

Amir Saeid Iravani, Iranian ambassador to the UN, described the US-Israel strikes as "war crimes". "This is not only an act of aggression; it is a war crime and a crime against humanity," he said.

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"The invocation of 'preemptive attack', claims of an imminent threat, or other unsubstantiated political claims are unfounded legally, morally and politically," Iravani added.

Maged Abdelaziz, the permanent observer of the League of Arab States to the UN, said Saturday's meeting came at a moment that "represents a glaring failure of the multilateral international system, a failure the League of Arab States has long warned against."

He said the Arab-Israeli conflict had expanded into a full-scale regional war and condemned military strikes carried out by Israel and Iran in several Arab countries.

Abdelaziz urged all states to "respect their obligations under international law, including the UN Charter, which clearly prohibits the threat or use of force against the territorial integrity or political independence of any state."

"Any use of force inconsistent with the purposes and principles of the United Nations, especially when it involves attacks on nuclear facilities, could have catastrophic consequences for entire populations," Abdelaziz said. He also called for an immediate halt to hostilities and efforts to prevent further escalation and a wider regional conflict.