Saudi troops fire shells towards Houthi positions from the Saudi border with Yemen on April 13, 2015. (Faisal Al Nasser/Reuters)

Iranian President Hassan Rouhani has suspended all "umrah," or lesser pilgrimages, to Saudi Arabia, a new mark of the intensifying animosities between Tehran and Riyadh. The move followed reports that two unnamed Iranian teenage pilgrims had been sexually assaulted in Jiddah airport while traveling back last month.

Every year, about half a million Iranians visit Islam's holy sites in Saudi Arabia, including the city of Mecca, outside the main season of pilgrimage, which is known as the hajj. Iran's ban on these "lesser" pilgrimages takes place at a heated moment: The Saudi-led bombing campaign in Yemen has been framed by the Saudis as an action against Iranian proxies in the region. The enmity between the two countries — an orthodox Sunni Sunni kingdom and a Shiite theocratic state — casts a shadow across the whole Middle East.

Last week, Iranian leaders, including Ayatollah Ali Khamenei, denounced the Saudi offensive and urged that the airstrikes be stopped.

Over the weekend, Saudi Foreign Minister Saud al-Faisal defended his country's intervention as a move to buttress Yemen's legitimate government, whose president, Abed Rabbo Mansour Hadi, has taken sanctuary in Riyadh in the face of advances by Shiite rebels.

"How can Iran call for us to stop the fighting in Yemen?" asked the the top Saudi diplomat at a news conference alongside French counterpart Laurent Fabius. "We came to Yemen to help the legitimate authority, and Iran is not in charge of Yemen."

As WorldViews discussed earlier, the Yemeni conflict did not start out as a war between Iranian and Saudi proxies. The Houthi rebels, who have loose Iranian backing, did not depend on Tehran when they launched their uprising more than a decade ago or when they took over the Yemeni capital, Sanaa, last year. Until recently, the only sectarian dimension to the chaos in Yemen involved Houthi clashes with al-Qaeda militants, who are Saudi foes as well.

The Houthis' rise has much more to do with Yemen's complex, fractious politics and the feebleness of Hadi's government, which was installed after a much-criticized Saudi-backed transition in 2012. Military units loyal to Ali Abdullah Saleh, Yemen's long-ruling strongman and Hadi's predecessor, are said to be backing the Houthi takeover. (The fact that Saleh spent years repressing the Houthis when in power is a snapshot of the opportunism of the moment.)

But in an op-ed published Monday in the New York Times, Hadi pinned all the blame on Iran, condemning Tehran's aims for "regional hegemony" and praising Saudi efforts for supposedly pulling Yemen back from "the brink of the abyss":

The Houthi rebels are puppets of the Iranian government, and the government of Iran does not care for the fate of ordinary Yemenis; it only cares about achieving regional hegemony. On behalf of all Yemenis, I call on the agents of chaos to surrender and to stop serving the ambitions of others...

If the Houthis are not stopped, they are destined to become the next Hezbollah, deployed by Iran to threaten the people in the region and beyond.

There are, undoubtedly, constituencies in the Islamic republic that would want Hadi's reading of events to be true, and for the Houthis to be as directly an Iranian proxy as Hezbollah, the influential Lebanese Shiite organization that the United States considers a terrorist group.

But it's been clear for quite some time that Hadi has had little to no genuine support from within Yemen and is, in many ways, a Saudi puppet. Last month, he fled his last redoubt in the southern coastal city of Aden as Houthi forces advanced against the remnants of his tattered army. The Riyadh dateline on Hadi's op-ed speaks volumes.

The Houthis themselves have repeatedly denied suggestions that they are an Iranian front and have condemned the Saudi campaign to restore Hadi — which has involved more than 1,200 airstrikes since it was launched late last month — as an act of aggression against the Yemeni people.

Whatever the case, it's taking a toll on the Yemeni people. On Monday, the humanitarian group Doctors Without Borders reported that its doctors had treated at least 800 Yemenis since the Saudi-led campaign began last month. The World Health Organization claims the airstrikes have killed at least 311 civilians since March 26.

Human Rights Watch issued a stern communique, urging an investigation into reports of war crimes and requesting U.S. help to "facilitate the delivery of humanitarian aid" to what is already one of the Arab world's poorest countries.

"The alarming civilian deaths and humanitarian crisis in Yemen should spur the Saudi-led coalition and the Houthis to get serious about protecting civilians," said Philippe Bolopion, the rights group's U.N. and advocacy crisis director.

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Saudi Arabia opens up a can of worms in Yemen

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