Saudi Arabia's King Salman elevated his 31-year-old son on June 21 to become crown prince, ousting his nephew in a seismic shift in the royal succession line. Prince Mohammed bin Salman, the new crown prince, will also become the kingdom's deputy prime minister. (Reuters)

Iran's state media has criticized changes to regional rival Saudi Arabia's royal line of succession announced Wednesday, calling them a “soft coup.”

A number of royal decrees proclaimed early on Wednesday that Saudi King Salman had elevated his 31-year-old son to become crown prince and second in line to the throne. While the timing was unexpected, the move itself was not: The new Crown Prince Mohammed bin Salman had been consolidating his power over the past two years at the expense of his cousin Mohammed bin Nayef, who formerly had been ahead of him in succession.

The moves sparked critical coverage in Iran, where state television ran a headline calling the move a “soft coup.” The semiofficial news agency Fars dubbed it a “political earthquake” and wrote that Nayef had been “ousted.” The website of English-language news agency Press TV ran a lengthy article that denounced Mohammed bin Salman's hand in policy, including the “bloody military campaign” in Yemen and the “extensive and jarring economic shake-up” currently underway in Saudi Arabia.

The new crown prince was barely known internationally when his father became king in January 2015. However, he was quickly given a wide range of powers as defense minister and leader of an economic council  — and often in these roles, he pushed moves that placed pressure upon Iran.

The Post's David Ignatius explains why Saudi Arabia is at a historic tipping point --- and why that matters for America. (Adriana Usero/The Washington Post)

Mohammed bin Salman is believed to have been the driving force behind a Saudi-led military campaign against Shiite rebels in Yemen that are alleged to be backed by Tehran, as well as a recent move to diplomatically isolate Qatar, which led to Iran sending food shipments to the tiny gulf state. The crown prince has also pushed for closer ties to President Trump, who often speaks critically of the threat posed by Iran.

In an interview conducted last month, the Saudi prince had suggested that Iran wanted to wrest control of Islam's holiest sites away from Riyadh and that there could be no dialogue with the regional Shiite power. “Instead we will work so that the battle is for them in Iran, not in Saudi Arabia,” Mohammed bin Salman told a reporter from the Saudi network MBC. The comments sparked an apparent response from Supreme Leader Ayatollah Ali Khamenei, who dubbed the Saudi leadership “idiots” whose policies would lead to “certain downfall.”

There have been serious doubts about the effectiveness of aggressive policies under Mohammed bin Salman. The military campaign in Yemen has cost Saudi Arabia billions and produced high levels of civilian casualties, but any victory over the Houthis still seems distant. Meanwhile, the attempt to isolate Qatar appears to have produced a split within the U.S. foreign policy world. While Trump has spoken approvingly of the policy and accused Qatar of links to terrorism, the State Department issued an unusual statement Tuesday that said it was “mystified” by the Saudi-led actions.

While the ambitious plans to limit government spending and wean the Saudi economy off oil have yet to produce similar conflict, they run the risk not only of fiscal failure but of pitting Mohammed bin Salman and other Saudi royals against the country's conservative religious establishment.

Saudi television showed Mohammed bin Nayef publicly pledging his loyalty to Mohammed bin Salman on Wednesday, suggesting for the time being at least the transition should be smooth. But it may not just be Iran which has doubts about the new crown prince — many in Washington knew and respected Mohammed bin Nayef as he had helped lead Saudi Arabia's campaign against al-Qaeda for years.

And there may be some in Saudi Arabia who have their own doubts, too. Iranian news outlets pointed to one anonymous Twitter account, which claims to share secrets from the Saudi elite and is now claiming that King Salman will step down within days. That account has frequently criticized Mohammed bin Salman, suggesting his impulsiveness could be dangerous.

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