RIYADH, Saudi Arabia — The Saudi royal family prizes stability as much as the oil that secures its wealth, but political upheaval across the Middle East has shaken the kingdom’s sense of balance, forcing it to press for radical change in Syria and confront a bid by longtime nemesis Iran to wield greater influence.

The decades-old rivalry between Sunni Muslim Saudi Arabia and Shiite-controlled Iran for prominence in the region is one of the volatile subplots embedded in the “Arab Spring."This was evident Thursday when Saudi Arabia and other Persian Gulf countries, which have complained of Iranian manipulation of the Shiite-majority government in Iraq, sent lower-level delegations to the Arab League summit in Baghdad.

Intrigue between Riyadh and Tehran has sharpened as Iran has accelerated its nuclear program. The kingdom blames Tehran for training Islamic militants and for stirring sectarianism in eastern Saudi Arabia and in neighboring Yemen and Bahrain. The bloodshed in Syria has enraged the monarchy, but also provided a moral cover as it attempts to undercut Iran by weakening its strategic proxy, Syrian President Bashar Assad.

Iran’s meddling “is very dangerous,” Saudi Foreign Minister Prince Saud al Faisal told The Times.

In a wide-ranging interview, Saud listed other highly charged issues, including Israel’sthreat to attack Iran’s nuclear program. His comments about the region’s precipitous change, including the ouster of longtime Saudi allies such as deposed Egyptian President Hosni Mubarak, illustrate how cautiously Saudi Arabia’s old guard is navigating this perilous new world.

Expressing Saudi fears that the Arab uprisings could ignite new unrest in the region, and even within the kingdom, the prince reflected on epoch-changing rebellions. “Revolutions have brought good things, and some revolutions have brought bad things,” he said. “The French Revolution was followed by a reign of terror.”

The Obama administration embraced the Arab revolts last year, a policy that strained relations with Riyadh. The strategic U.S.-Saudi partnership, as both sides like to call it, has improved somewhat since. Both countries share similar concerns about Iran and Syria, and seek to calm oil markets to prevent further pressure on the global economy.

Led by a king in his late 80s and a cadre of top princes not much younger, the House of Saud presides over a nation anxious about succession and a young generation craving greater freedom from the kingdom’s rigid form of Islam and an oppressive Interior Ministry often cited for human rights abuses.

Saudi Arabia’s decisions to send troops to help crush a Shiite rebellion in Bahrain and to grant refuge last year to deposed Tunisian President Zine el Abidine ben Ali are testaments to its resistance to shifting regional dynamics. The message was stark: The kingdom stands by its allies — no matter how corrupt — and will not tolerate antigovernment protest.

But some leaders, most notably Assad, whose violent repression of his people has jarred the world, are expendable to Saudi Arabia and other Persian Gulf countries in their larger strategic struggle against Iran. Removing the Syrian president and his Shiite-offshoot Alawite regime could bring Syria’s majority Sunnis to power, and limit Iran’s reach in Lebanon and the Gaza Strip, where it backs the militant group Hamas.

Prince Saud has urged the international community to arm Syria’s rebels, but he denied reports that the kingdom was secretly sending weapons through Jordan. “You must at least allow those who are being killed to protect themselves,” he said. “Perhaps that will change the mind of the government if they see that.”

He was animated in criticizing world powers, especially Russia and China, for not stopping Assad’s army from its pummeling of Homs and other Syrian cities. Moscow and Beijing, which increasingly needs Saudi oil to fuel its economic growth, blocked attempts by the United Nations to impose harsher sanctions on Damascus.

“We don’t understand what objectives they [Russia and China] are trying to pursue,” Saud said. “If it is stability they’re looking for, certainly stability cannot be achieved by such a policy of bloodletting. If it’s protecting their interests, they are losing public opinion in the region very quickly.”

On Tuesday, the Assad regime agreed to a cease-fire negotiated by U.N. envoy Kofi Annan. But the government has broken past pledges, and fighting continued in the conflict, which the United Nations says has claimed more than 9,000 lives. The fate of Syria is central to the tension between Riyadh and Tehran, which has framed much of the politics in the region since Iran’s 1979 revolution.

Saudi Arabia is frustrated over how to counter Iran’s maneuverings, which include expanding its influence with Iraq’s Shiite-dominated government, training Islamic militants in Lebanon and arming Houthi rebels in Yemen. The kingdom’s army battled the rebels in 2009 along the Saudi-Yemen border. Riyadh also alleges that Tehran is aiding an Al Qaeda branch in Yemen for attacks on oil targets inside the kingdom.

Saud said, however, that Iran’s alliances with countries such as Iraq and Syria were not stronger than the allegiances those nations have to the Arab world.

“Syria and Iraq are Arab countries, and whatever change happens [they] will be coming back to the Arab fold and not going toward Iran,” he said.

The mistrust has been exacerbated by Iran’s nuclear ambitions. Iran says its nuclear program is for civilian proposes, but the U.S. believes the goal is to produce a bomb. The fear is that Tehran’s nuclear aspirations will spur Arab countries to follow suit to protect themselves. Concern for its security and efforts to counter Iran partly influenced Saudi Arabia’s decision to buy $60 billion worth of fighter aircraft, helicopters and other equipment from the U.S. in 2010.

Deep economic sanctions imposed on Iran have led to threats by Tehran to close the Strait of Hormuz, which would affect shipping lanes for all gulf countries. The Saudis have attempted to allay fears, saying that there is enough oil on the market and that it would boost output if necessary.

Saudi Arabia and other gulf states are more alarmed by the specter of an Israeli strike on Iran’s nuclear installations. Such an attack would probably shift international condemnation against Iran to Israel, spur terrorism against Jerusalem and possibly lead to a wider regional war. Saud said that Israel’s rhetoric is reckless and that its security is not in jeopardy.

“Who is threatening Israel with atomic bombs? Which Arab countries are arrayed on the border of Israel? Is there a threat to Israel’s security?” he asked. An Israeli attack on Iran without considering the wider consequences “would be an act of extreme uncaring for the region and its stability,” he said.

Saud said his kingdom has been closely following the global debate over Washington’s perceived loss of influence.

“People are saying that America is losing its power because it’s not able to influence events in other countries,” he said. “What you hear in the debate is that because America is not using its military force to solve things it’s losing power.”

He said, however, that the White House was turning “to the power of ideas,” which is “more important that the power of artillery.”

But even that, he suggested, can be inconsistent, especially when it comes to U.S. support of Israel and lack of progress on a Palestinian state. Saud said the Arab world was encouraged by President Obama’s speech to Muslims in Cairo in 2009, which struck a more conciliatory note than policies of theGeorge W. Bush administration.

“We thought, thank God, America is coming back,” he said. “But I think his program was abrogated before it was fulfilled.”

jeffrey.fleishman@latimes.com