A Houthi missile fired at Riyadh may be considered an act of war by Iran, and Saudi Arabia will not tolerate any infringement of its national security, senior Saudi officials said on Monday.
“The Kingdom reserves the right to respond in a timely manner to the hostile actions of the Iranian regime,” Saudi Foreign Minister Adel Al-Jubeir said.
“Iranian interventions in the region are detrimental to the security of neighboring countries and affect international peace and security. We will not allow any infringement of our national security.”
Iran supplied the ballistic missile fired into Saudi Arabia on Saturday night by Houthi rebels in Yemen. Saudi defense forces intercepted the missile and shot it down over King Khaled International Airport in Riyadh, and there were no casualties.
“Iran’s role and its direct command of its Houthi proxy in this matter constitute a clear act of aggression that targets neighboring countries, and threatens peace and security in the region and globally,” the Saudi-led coalition in Yemen said on Monday.
“Therefore, the coalition’s command considers this a blatant act of military aggression by the Iranian regime, and could rise to be considered as an act of war against the Kingdom of Saudi Arabia.
“The coalition command also affirms that the Kingdom reserves its right to respond to Iran at the appropriate time and in the appropriate manner.”
The Coalition Forces Command ordered the temporary closure on Monday of all air, sea and land ports in Yemen, except for aid workers and humanitarian supplies.
Col. Turki Al-Maliki, spokesman for the coalition, produced evidence on Sunday that Iran supplied weapons and technology to the Houthis, including ballistic missiles, launchers, aerial drones, land and naval mines and improvised explosive devices.
Bahraini Foreign Minister Sheikh Khaled bin Ahmed Al-Khalifa said Iran was a danger to the region, and the Harvard scholar and Iranian affairs expert Majid Rafizadeh said the international community should hold Tehran accountable.
“Compromises, concessions and diplomatic maneuvering don’t work with the Iranian regime,” he told Arab News. “Iranian leaders view concessions as weakness.”
He called for a combination of economic sanctions, political pressure and enhanced monitoring of Iran’s illegal activities. “Tehran’s exports and imports should be closely examined and restricted. The US, EU and Arab powers should form a military front, like NATO, as a bulwark against the Iran regime.”
Rafizadeh said Iran was the leading state sponsor of terrorism. “The UN should invoke UN Resolution 2231 and immediately punish Tehran for violating it. Otherwise, Tehran’s belligerent behavior will continue to grow. This can turn the regional conflict into a conflagration.”
UN Security Council Resolution 2231 adopted the 2015 Iranian nuclear deal, but also imposed restrictions on Iran’s use of some ballistic missiles.
Thomas Mattair, executive director of the Middle East Policy Council in Washington, told Arab News: “Iran should not expect to be able to facilitate attacks on Saudi Arabia without paying some consequences.”
Dr. Hamdan Al-Shehri, a Saudi political analyst and international relations scholar in Riyadh, said the international community should have prevented Iran from creating havoc in the region.
“Things would not have reached this pass if the world community had taken measures against Iran and its arming of militias such Hezbollah and the Houthis,” he told Arab News. “The world’s inaction led Iran to believe that it can basically get away with murder.”
He condemned Iran for first attacking Makkah in July, and now Riyadh. “They want to kill innocent people and spread terror; this is their only business.”
The world community, and specifically the US and Russia, must pressurize Iran to give up its hostility to Arab countries, Al-Shehri said. “Now is the time to act.”  
Al-Shehri said the missile attack on Riyadh was a “declaration of war” on Saudi Arabia.  
“Saudi Arabia will not sit idle and will not wait for the international community to do nothing,” he said. “Foreign Minister Adel Al-Jubeir has made it clear that Saudi Arabia, in coordination with its Arab allies, reserves the right to defend its sovereignty and its people.”
Al-Shehri said all options were on the table and all measures were being explored. “The Saudi leadership will decide what option and measures to go for and when,” he said. “One thing is clear, this Iranian-Hezbollah-Houthi provocation and attack will not go unpunished.”
Among the options, he said, was directly confronting Iran. “A fitting Saudi response will come at a time and place of its choosing.”
David Pollack, a scholar at the Washington Institute for Near East policy, said Saudi Arabia “generally has a valid case. The Arab coalition and its international partners, including the US, should intensify maritime and land interdiction efforts, including via Oman.”
Aaron David Miller, vice president for new initiatives and Middle East program director at the Woodrow Wilson Center for International Scholars, speculated that Saudi Arabia had reached a “firm understanding” with the US that should tensions with Iran escalate, “the US will be there to support” the Kingdom.
King Salman and President Donald Trump spoke by phone on Saturday and discussed the Houthi missile attack and Iran’s involvement in the region