Saudi Arabia’s new monarch, King Salman, announced a major shift within the nation’s royal family on Wednesday, replacing his anointed heir with his nephew and naming his own son as the second in line to the throne.

The royal decrees, read on state television before dawn, thrust a younger generation of princes closer to the pinnacle of power at a time of growing challenges for the Western-allied kingdom.

On a regional level, Saudi leaders are facing pressure from several quarters — extremist groups such as the Islamic State; Iran, the country’s increasingly influential rival; and rebels who have seized much of neighboring Yemen.

At home, Saudi Arabia must cope with declining oil prices and the difficulties of ensuring employment for a growing population. About half of Saudi citizens are younger than 30.

The new line of succession signals a potential ideological shift as the kingdom moves away from policies matched lock-step with Washington’s and increasingly establishes its own security and foreign affairs initiatives.

New heirs to the Saudi throne

“This change positions [Saudi Arabia] toward leaders who feel that they are facing serious threats from Iran as well as from issues like terrorism,” said Riad Kahwaji, head of the Dubai-based Institute for Near East and Gulf Military Analysis. “They feel they have no choice but to be more assertive with their foreign policy.”

In the decrees, Salman promoted his nephew, Mohammed bin Nayef, 55, from deputy crown prince to crown prince. Unless there are further shake-ups, that means that Nayef — currently the interior minister — will become king when the 79-year-old Salman dies.

Salman also named his son, Mohammed bin Salman, as deputy crown prince, putting him second in line to the throne and ensuring that the kingdom’s future rulers will come from Salman’s own branch of the extensive royal family. Mohammed bin Salman, currently the defense minister, is believed to be about 30.

The changes represent the biggest royal shake-up in Saudi Arabia in years and offer yet another indicator that Salman is proving a more energetic and decisive leader than his predecessor, King Abdullah, who died in January at age 90.

A major driver of that assertiveness is concern over Iran, a Shiite powerhouse and the chief rival of predominantly Sunni Saudi Arabia. Riyadh has grown increasingly alarmed by Tehran’s expanding influence in Iraq and its role in Syria’s civil war, in which it is bolstering forces loyal to the regime of President Bashar al-Assad.

The Saudi government’s decision to launch an air war against Shiite rebels in Yemen in March is widely seen in the region as an example of a turn to a more forceful foreign policy.

Mohammed bin Salman, who was appointed defense minister after Salman took power in January, has assumed a high-profile role in the Yemeni military campaign, which Saudi leaders have portrayed as necessary to counter Iranian influence in the region. Iran denies it provides direct aid to the Yemeni rebels.

The succession moves squeeze out Prince Muqrin, the late King Abdullah’s choice to succeed Salman. Abdullah had named Muqrin, his younger half-brother, as deputy crown prince two years ago, in what was widely seen as an effort to secure the crown for an ally of his own sons.

Nayef is the first of the grandchildren of the late Abdul Aziz ibn Saud, the founder and first king of Saudi Arabia, to move to the doorstep of the country’s top ruling position.

Whether the succession will proceed exactly as Salman plans is in question, however.

King Abdullah set a precedent when he named a deputy heir. Salman, however, has set his own standard by dismissing his predecessor’s choice for the No. 2 person in line for the throne.

There have long been concerns that the transfer to the second generation of the family could trigger destabilizing rivalries between the hundreds of princes potentially eligible to rule the strategically important nation, one of closest Arab allies of the United States.

Salman also replaced 75-year-old Foreign Minister Prince Saud al-Faisal, who had been in the job for four decades. His successor is the ambassador to the United States, Adel al-Jubeir, who is 53. The king announced other changes that will bring younger blood into the kingdom’s aging administration.

Mohammed Obeid, a political analyst from Lebanon, said Saudi officials have grown increasingly alarmed over a potential U.S.-Iran rapprochement as those two countries negotiate an agreement over Tehran’s nuclear program.

“These new leaders in Saudi are moving in a different direction than the United States, and their policies in the region are an example of this,” Obeid said.

Nonetheless, Nayef has strong ties with officials in Washington. Those links were cultivated in his role over the past decade in overseeing domestic counterterrorism programs, which included crackdowns on members of al-Qaeda as well as rehabilitation programs for militants.

According to Saudi media reports, Nayef has been targeted in at least four assassination attempts by al-Qaeda militants, including one in 2009 that was carried out at his home in the city of Jiddah.

“He’s clearly well known for the counterterror campaign, he’s responsible for Saudi Arabia’s de-radicalization program, and he’s very close to policymakers in Washington,” said Theodore Karasik, a Dubai-based expert on Middle Eastern military issues. “It’s assumed that he’s in close contact with them constantly.”

Still, there have been tensions with the U.S. government over allegations of human rights abuses committed by Saudi authorities against domestic dissidents and over Saudi practices such as public beheadings of convicted criminals.

Daniela Deane in London contributed to this report.

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