The international community joined in unison Sunday to condemn the deadly Houthi attack on Saudi capital Riyadh.

U.N. and EU leaders voiced shock at the attack and warned against an escalation in the deadly conflict.

Secretary-General Antonio Guterres said he was "deeply shocked" by Saturday's attack on Riyadh's airport, which killed 12 people and wounded over 300, according to aviation authorities.

"Attacks on civilians and civilian infrastructure are a violation of international law. These attacks must cease immediately," Guterres said in a statement.

U.S. President Donald Trump said Saturday that Washington may join Saudi strikes against the Houthis in Yemen following the attack.

Asked by reporters whether he had decided to take part in the strikes, Trump said: "We may. We're going to look at it. We just found out about the recent attack. We will make a decision. We move very quickly."

EU chief Ursula von der Leyen called the attack a "dangerous escalation" and said the Iran-backed group must halt strikes on civilian targets.

"These attacks by Iran's proxies are pushing the region into a spiral of violence. They are destabilizing crucial global transport and energy nodes with shockwave sent through the world," von der Leyen said.

"These murderous attacks at civilians must stop at once," she said, adding the EU stands in "solidarity with Saudi Arabia."

German Foreign Minister Johann Wadephul said he "firmly condemns" the attack, which he described as "a terrorist act against Saudi Arabia and civil aviation."

"Our thoughts are with the victims and I send my sincere condolences to their loved ones," he wrote on X.

Meanwhile, U.K. Defense Minister Wes Streeting said the attacks were "contemptible" and a "dangerous escalation"

France also condemned the "heinous attack" and stressed "total solidarity" with Saudi Arabia.

France, which is already lending troops and military equipment to Saudi Arabia, "will continue to remain by its side in its defense of its territory and its infrastructure," a Foreign Ministry statement said, calling on the Houthis to cease their attacks.

Meanwhile, Pakistan's Prime Minister Shehbaz Sharif strongly condemned the deadly attack on Saudi capital's international airport.

"Attacks targeting civilians and vital infrastructure are utterly unacceptable and pose a serious threat to regional peace and stability," Sharif posted on X, describing the attack as "heinous" and reaffirming Pakistan's "steadfast commitment to Saudi Arabia's sovereignty, territorial integrity."

Pakistan is close ally of Saudi Arabia and are part of the Mecca mutual defense pact alongside Türkiye.

Another Saudi ally, Syria also condemned "in the strongest terms" Saturday's deadly attack on King Khalid International Airport.

It stressed that the security of Saudi Arabia is an "integral part of the security of Syria and the entire region."

In a statement released on X, the Syrian Foreign Ministry described the attack as "a violation of the Kingdom's sovereignty and a direct threat to its security and stability, as well as to the safety of civilians, civilian facilities, and air navigation."

Malaysian Prime Minister Anwar Ibrahim "unequivocally denounced" the attack, saying "there can be no justification for attacks against civilians and civilian infrastructure."

Anwar said on X that putting innocent lives at risk "can only deepen the suffering already wrought by this conflict and carry it into places that should remain beyond its reach."

He also said Malaysia stands in solidarity with Saudi Arabia and its people "at this perilous hour," and that Kuala Lumpur remains "steadfast in our hope that diplomacy and reason will prevail before the conflict widens still further."

Bangladesh also "strongly and unequivocally" condemned the attack in an official statement. Two Bangladeshi nationals have been killed in the strike.

"Attacks endangering civilian lives and targeting civilian infrastructure are unacceptable and must cease immediately," the Bangladesh Foreign Ministry said.

The Muslim-majority South Asian nation also called for an "immediate cessation of hostilities, the protection of civilians and civilian infrastructure, and a peaceful resolution of the ongoing crisis through dialogue and diplomacy, in the interest of regional peace, security and stability."

Meanwhile, Saudi Arabia on Sunday kept its main international airport closed and moved Riyadh schools online as Yemen's Houthi rebels threatened new airstrikes across the kingdom.

Saturday's strike on King Khalid International Airport in Riyadh marked a major escalation in the war between Yemen's Iran's-backed Houthis and the kingdom and further complicated sputtering efforts to halt the U.S.-Iran war.