Iranian and Syrian officials blamed Israel for Monday's attack, though Israel declined to comment.

Iran vowed a stiff response, with fears of even further violence between Israel and Tehran's allies amid the Gaza war.

"China condemns the attack," Foreign Ministry spokesperson Wang Wenbin said, in response to a question from a journalist.

"The security of diplomatic institutions cannot be violated, and Syria's sovereignty, independence and territorial integrity should be respected," he said.

China is a close partner of Iran, its largest trade partner, and a top buyer of its sanctioned oil.

Iran's Islamic Revolutionary Guard Corps said seven of its members were killed in the strikes, including Brigadier General Mohammad Reza Zahediback and another high-ranking officer, Brigadier General Mohammad Hadi Haji Rahimi.

Britain-based war monitor the Syrian Observatory for Human Rights said 11 people, including several Guards members, were killed when "Israeli missiles... destroyed the building of an annex to the Iranian embassy".

Chinese state media blamed Israel for the strikes. Beijing's strategic ally Russia had also earlier accused Israel.

- 'Shocked' -

China is one of Syria's main international allies.

In September last year China became one of only a handful of countries outside the Middle East that Syrian President Bashar Al-Assad has visited since the 2011 start of a civil war that has since killed more than half a million people and displaced millions more.

Meanwhile, China also condemned a strike in the Gaza Strip that killed seven aid workers who, according to their US-based charity, were delivering desperately needed food aid in the devastated Palestinian territory.

China, historically sympathetic to the Palestinian cause, has been calling for a ceasefire in Gaza since the war began when Hamas militants attacked Israel on October 7.

"China opposes all acts that harm civilians, damage civilian facilities, and violate international law," Wang said.

"We are shocked by the attack on international rescue workers in Gaza and condemn it," he said.

"We express our deep condolences to the victims," Wang added.

"Civilians should not be targets of attacks, and the safety of international humanitarian rescuers should not be threatened," he said.

Beijing said it urged "all parties concerned, especially Israel" to "make every effort to ensure the safety of civilians, hospitals and other civilian facilities specially protected by the Geneva Conventions, and prevent a more serious humanitarian disaster in the Gaza Strip".

The war began on October 7, triggered by Hamas's unprecedented attacks which resulted in about 1,160 deaths in Israel, mostly civilians, according to an AFP tally based on Israeli official figures.

Israel's retaliatory campaign has killed at least 32,845 people, mostly women and children, according to the health ministry in Hamas-run Gaza.

Palestinian militants also seized around 250 hostages. Israel believes about 130 remain in Gaza, including 34 presumed dead.