The United States has called on the United Nations to hold Iran accountable for allegedly supplying Yemeni rebels with missiles that have been fired at Saudi Arabia, the main backer of Yemen's government in a three-year-old civil war.
U.S. Ambassador to the UN Nikki Haley said on November 7 that Saudi Arabia had provided information showing a missile fired in July was an Iranian Qiam, which she described as "a type of weapon that had not been present in Yemen before the conflict."
Haley said a ballistic missile shot down over Saudi Arabia on November 4, which precipitated a sharp escalation of tensions between Riyadh and Tehran this week, "may also be of Iranian origin."
Haley said that by providing weapons to Yemen's Shi'ite Huthi rebels, Iran's Islamic Revolutionary Guards Corps had violated two UN resolutions, one of which prohibits Tehran from supplying weapons without UN Security Council approval, and another which bans the supply of weapons to various Huthi leaders.
"We encourage the United Nations and international partners to take necessary action to hold the Iranian regime accountable for these violations," she said.
"The United States is committed to containing Iran's destabilizing actions, and will not turn a blind eye to these serious violations of international law by the Iranian regime," Haley added.
Iran, while openly supporting the Huthis, has denied arming them. Iran's Defense Ministry and Revolutionary Guards both denied the U.S. and Saudi accusations on November 7.
Before Haley spoke, Saudi Arabia's Crown Prince Muhammad bin Salman accused Iran of supplying missiles to the Huthis, in what he said was a "direct military aggression by the Iranian regime," which "could be considered as an act of war," in remarks carried by the Saudi Press Agency.
The Saudi-led coalition, which has backed the Yemeni government with a devastating bombing campaign against the rebels since 2015, has tightened its blockade of rebel-held areas in response to the weekend missile launch in what it said was an effort to stop the smuggling of arms to the rebels.
Meanwhile, the Yemeni rebels have threatened to attack ports and airports not only in Saudi Arabia but in the United Arab Emirates, another coalition member, in retaliation.
Iranian Foreign Ministry spokesman Bahram Qassemi on November 7 said the Saudis' "insinuations are false, destructive, irresponsible, and, above all, provocative."
Instead of aggravating the situation with such "absurd allegations," Qassemi said, the Saudis should seek an end to the violence in Yemen through diplomatic channels.
One senior Iranian official questioned how Iran could sneak missiles into the heavily blockaded country, as alleged.
"Is it possible from a military point of view to send a very long missile to Yemen when all the ships surrounding Yemen are very much alert to intercept any shipments of arms to Yemen?" this official asked Reuters. "The Saudis and their supporters know this is a fake story."
The European Union's foreign-policy chief, Federica Mogherini, called the recent escalation of tensions between the two Middle Eastern neighbors and rivals "extremely dangerous," and called on all sides to back down and seek "a minimum of common ground."
"I know that this is not the wind that is blowing as the majority voice in the world of today," Mogherini told reporters on a visit to Washington on November 7.
"But allow me to bring a little bit of wisdom as the European voice in a world that seems to go completely crazy here: It's dangerous." she said.
Saudi Arabia and Iran back opposing sides not only in Yemen's civil war but in power struggles in Syria, Iraq, Lebanon, and elsewhere.
The growing tensions between the two major oil producers has helped push oil prices this week close to two-year highs and spooked global stock markets.
The missile, which was intercepted near the Riyadh international airport on November 4, was the first to reach the Saudi capital and underscored the growing military capability of the Yemeni rebels as well as the increasing fallout for Saudi Arabia from its involvement in the Yemeni war.
UN and humanitarian aid officials warned on November 7 that the Saudi-led blockade of Yemen threatens to deepen the desperation of 7 million people the UN has said already are on the brink of famine in Yemen.
"If these channels, these lifelines, are not kept open, it is catastrophic for people who are already in...the world's worst humanitarian crisis," said Jens Laerke, a spokesman for the UN's humanitarian coordination office in Geneva.
Aid officials say their shipments to civilians in Yemen have been blocked since the weekend.
The International Committee of the Red Cross also urgently called for humanitarian access to be restored.