China is pushing for a return to talks and an immediate ceasefire as the Iranian conflict takes an intense turn ahead of the United States-imposed deadline on Tehran.

During a news conference on Tuesday, Chinese Foreign Ministry spokeswoman Mao Ning said China hopes for all the parties to show sincerity and quickly end this war that should not have happened in the first place.

She said the root cause of the tension lies in the unlawful use of force by the US and Israel against Iran, which violates international law.

Mao said force cannot bring peace and a political settlement is the only way forward, adding that the top priority is to bring an immediate end to the military operations and return to dialogue and negotiation, so as to fundamentally resolve the issues and restore peace and stability in the Gulf region.

She said the situation in the Middle East continues to deteriorate, with hostilities still escalating and dragging down the global economy and energy security, which has caused deep concern in the international community.

Since the outbreak of the conflict, China has maintained an objective, fair and balanced position and worked consistently to promote a ceasefire and an end to the fighting, Mao said. Foreign Minister Wang Yi has held 26 phone calls with parties including Iran, Israel, Russia and Gulf countries, while the Chinese government's special envoy on the Middle East issue has engaged in shuttle diplomacy in the region, she said.

Mao added that China and Pakistan recently put forward a five-point initiative, reflecting the broad consensus of the international community in support of peace and an end to the war.

Reza Amiri Moghadam, Iranian ambassador to Pakistan, said in a post on X on Tuesday that Islamabad's "positive and productive endeavors" to stop the war were approaching a "critical, sensitive stage".

The United Nations said it was alarmed by an ultimatum Washington gave if Tehran continued to block the Strait of Hormuz, as a deadline the Trump administration had set inched closer.

"We were alarmed by the rhetoric seen in that social media post that threatened American attacks on power plants, bridges, and other infrastructure, should Iran not agree to a deal," Stephane Dujarric, spokesperson for the UN secretary-general, said at a news conference on Monday. He reiterated that the secretary-general "has been very clear on issues regarding international law", and he urges yet again all parties "to abide by their obligations regarding the conduct of these hostilities".

Iran has set preconditions for talks on a lasting peace with the United States, including an immediate halt to strikes, guarantees that attacks will not be repeated and compensation for damage, Reuters reported on Tuesday, citing an anonymous senior Iranian official. The official said Tehran rejects any temporary ceasefire with the US.

Shipping fees

He added that a permanent peace deal should allow Iran to demand fees for ships passing through the Strait of Hormuz, which would vary depending on the type of ship, its cargo and prevailing conditions, according to the report.

On Monday, Pakistan proposed a two-stage plan to end the US-Israeli attacks on Iran, which included the reopening of the Strait of Hormuz, Reuters reported.

US President Donald Trump threatened on Tuesday morning that Iran's "whole civilization will die tonight", the deadline he set for Iran to make a deal and reopen the Strait of Hormuz, marking a possible sharp escalation in the US-Israeli conflict with Iran.

"A whole civilization will die tonight, never to be brought back again. I don't want that to happen, but it probably will," Trump wrote in a post on his social media platform Truth Social.

As Trump's deadline loomed, Iranian President Masoud Pezeshkian took to X on Tuesday, saying over 14 million proud Iranians "have, up to this moment, declared their readiness" to sacrifice their lives in defense of their country.

According to a post by journalist Barak Ravid of the news site Axios on Tuesday, citing a US official, the US carried out "strikes on military targets" on Kharg Island located off Iran's western coast.

The Iranian Red Crescent said US-Israeli attacks hit 17 civilian areas across Iran on Tuesday and said in a statement on X that there was no justification for attacking civilians, reiterating that international law states that attacking defenseless civilians is a war crime. At least 15 people were killed overnight, Iranian media reported.

Attempts to de-escalate the situation are almost immediately overshadowed in the region by nonstop, intense tit-for-tat strike threats.

On Tuesday, Gulf countries spent another day repelling attacks in their respective territories with Saudi Arabia's ministry of defense reporting the interception and destruction of at least 18 drones "during the past hours". The King Fahd Causeway, which connects Saudi Arabia to Bahrain, was briefly suspended after Iranian attacks targeted Saudi Arabia's Eastern Province, but was reopened a few hours later.