Iran's security chief on Wednesday warned the United States would face a "new strategy" from Tehran in the Middle East war after the heaviest exchange of attacks between the foes in weeks.

"You will soon see that Iran's new strategy on the battlefield, in diplomacy and in confronting the economic blockade will shatter your foundations," Iran's Supreme National Security Council Secretary Mohsen Rezaei posted on X.

Chinese President Xi Jinping told his Egyptian counterpart on Wednesday that "external interference" in the Middle East should be opposed, Beijing's state media reported, following talks in Cairo between the two leaders.

"We must uphold the principle that the people of the Middle East are the masters of their own affairs, oppose external interference (and) support regional countries in strengthening dialogue on peace and security," Xi told Egyptian President Abdel Fattah al-Sisi, according to Chinese state news agency Xinhua.

Iran's top negotiator Mohammad Bagher Ghalibaf on Wednesday called the United States "Satan" after an attack on a wedding ceremony in the country's south.

"Minab school: children massacred. Lamerd sports hall: kids slaughtered. Kouhestak wedding: children killed with families. If a power acts like Satan, picks targets like Satan, and kills like Satan, it's Satan. Shields a junior Satan that does the same? It's THE Great Satan," said Ghalibaf in a post on X.

Iran's Revolutionary Guards said on Wednesday that four personnel were killed in a U.S. attack on the western province of Kermanshah.

"Four fighters of the IRGC Aerospace Force in Kermanshah province were martyred in an attack by the U.S. regime," the Guards said in a statement carried by Fars news agency, using their acronym.

Iranian media reported that the country's military had launched a "decisive operation" against U.S. targets in the region on Tuesday, as Washington carried out a fresh round of strikes.

The Tasnim news agency said a "decisive operation by Iran's armed forces in response to the U.S. enemy has begun. The U.S. bases and interests in the region are being targeted by Iranian missiles and drones."

The Iranian Red Crescent said on Tuesday that four people including a child were killed and over 50 people were wounded by a U.S. attack while attending a wedding in the south.

"Following a US missile attack, shrapnel hit a residential home in the city of Kuhestak, in Sirik county of Hormozgan province, where a wedding celebration was taking place," the Red Crescent said in a post on X.

US forces struck Iran on Tuesday and President Donald Trump vowed a "much harder" response to any counterattacks, as exchanges of fire between the two sides threatened to reignite their smoldering conflict.

Syrian authorities said at least five people were killed in northwest Idlib province on Tuesday when a vehicle carrying munitions exploded.

A government source told AFP on condition of anonymity that the vehicle belonged to a local arms dealer in the town of Binnish, without providing further details.

The United Nations' food agency said Tuesday it is halving food assistance in the Israeli-occupied West Bank because of severe funding shortages and warned it may be forced to make further cuts in Gaza, where it supports 1.5 million people.

The U.N. World Food Programme said it will reduce assistance in the West Bank from 400,000 people to 200,000 beginning this month. In Gaza, it reduced the value of cash assistance by 40% for 375,000 people in July and said additional cuts will be unavoidable unless it secures new funding.

Mediator Qatar on Tuesday urged the United States and Iran to return to negotiations after they renewed tit-for-tat attacks.

On Sunday, the U.S. carried out strikes on an Iranian island in the Strait of Hormuz, with Tehran quickly retaliating by attacking U.S. military targets in the Middle East.