Saudi Arabia's King Salman arrived in Moscow on Wednesday for a state visit, and Russian officials have prepared an impressive reception for the 81-year-old royal: The Russian capital will celebrate a highly publicized “Saudi Culture Week” as the king arrives, and the Saudi delegation, which typically travels in a grandiose style, is taking over the entire Moscow Ritz-Carlton.

The sense of occasion is understandable. This is the first official visit by a Saudi king to Russia in the two nations' histories. And it will be watched closely around the world — perhaps especially in Washington.

The United States has been Saudi Arabia's most important ally for more than 70 years. In contrast, Riyadh forged relations with Moscow only after the collapse of the Soviet Union. Even then, it took a while for things to warm up: Although Russian President Vladimir Putin visited the Saudi capital in 2007, then-King Abdullah didn't repay the favor.

Times have changed. Abdullah died in 2015, leaving Salman and his powerful young son, Crown Prince Mohammed bin Salman, in charge. Amid geopolitical uncertainty, with U.S. global leadership questioned and oil prices depressed, Saudi Arabia and Russia appear to have reconsidered their arm's-length relationship and moved toward something closer.

“The Saudi-Russian energy relationship is part of a larger nexus of mutual interests,” said Theodore Karasik, a senior adviser with Washington-based Gulf State Analytics, noting that Russia had been working on this relationship “under America's nose” for a decade, while Mohammed has visited Russia twice recently.

For the two largest oil producers in the world, much of the focus during the trip will be on energy politics. Saudi Arabia and Russia are expected to reach an agreement to cooperate on oil production, probably finalizing a $1 billion fund to invest in energy projects. Saudi Arabia, which is in the process of diversifying its economy, is particularly keen for outside investment.

But the two oil giants most probably won't stick to business alone. Moscow has become an undeniable political force in the Middle East. “There is little doubt that Saudi Arabia greatly values its relations with Russia and views them as multidimensional in nature,” said Fahad Nazer, a political consultant to the Saudi Embassy in Washington who does not speak on its behalf.

Of particular interest will be the shifting realities in Syria, where Moscow backs the government and Saudi Arabia and the United States back the opposition. As recently as last year, Russia's backing of President Bashar al-Assad and the influence of Iran and its proxies in Syria was a major bone of contention with Saudi Arabia. But, again, realities have changed.

“The Saudis are basically conceding that Assad will remain in power, but now hope to gain Russian help in keeping Iranian influence in Syria (and elsewhere) limited,” Mark Katz, a Russia specialist at the Schar School of Policy and Government at George Mason University, wrote in an email. “They will hold out the prospect of Saudi trade and investment as an inducement. It is not clear, though, that Moscow actually can do much to limit Iranian influence in Syria. And if the Saudis think that Moscow can't or won't, the Saudi trade and investment will not materialize.”

What this means for the United States is unclear. Salman's visit to Russia comes at a time of heightened tensions between Moscow and Washington. Although President Trump has embraced Saudi Arabia, even making the country his first foreign stop as leader of the United States, some analysts have suggested that Riyadh may be looking toward Russia because of uncertainty about Washington's intentions in the Middle East.

“The Saudis recognize that Russia is back as a major player in the region with their victories in Syria,” said Bruce Riedel, a senior fellow at the Brookings Institution and a former senior CIA analyst. He added, “A dialogue with Putin is also a hedge on their bet on Trump, who has disappointed them on Qatar,” which is embroiled in a political dispute with several Arab states, including Saudi Arabia.

Would Saudi Arabia trade its lengthy relationship with the United States, born all those years ago from a Suez Canal meeting between President Franklin D. Roosevelt and the first Saudi king, for a new one with Putin's Russia? Probably not. But the kingdom has shown itself willing to dramatically reconsider some aspects of its society recently, from loosening the oil industry's stranglehold on the economy to allowing Saudi women to drive, long a sticking point in the country's culture wars.

Standing closer with Russia may be easier than either of those goals. “Generally speaking, there is wide support in Saudi Arabia for strengthening and broadening political, economic and cultural ties with Russia,” Nazer said.

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