(Bloomberg) --

The sultan of Oman landed in Saudi Arabia on Sunday in the first visit by an Omani leader in over a decade, a sign of shifting alliances in the Persian Gulf as the kingdom reaches out to states with closer ties to regional rival Iran.

Skyscrapers in the Saudi capital, Riyadh, were lit up in red and green, the colors of the Omani flag, to celebrate Sultan Haitham bin Tariq’s arrival. The visit to the city of Neom, where he was greeted by Saudi Arabia’s de facto ruler, Crown Prince Mohammed bin Salman, coincides with the opening of the first-ever land crossing connecting the countries as Oman tries to diversify trade routes.

The Saudi cabinet also authorized officials to prepare and sign draft agreements with Oman in a slew of fields including commerce, culture, investment promotion and post and transport.

“There’s been a lot of work behind the scenes to try to build the foundation of something much more significant between the Saudis and Omanis,” said Ayham Kamel, head of the Middle East and North Africa at the political risk consultancy Eurasia Group. “Sultan Haitham is viewed in Riyadh as leaning toward Saudi in terms of Gulf affairs.”

A closer relationship could be an economic boon for Oman, which is struggling to diversify its economy away from oil. It also comes as Prince Mohammed reaches out to states once held at a distance over differences in their approach to Iran. Saudi Arabia has forged closer ties with Iraq, hosting the prime minister in March, and reconciled this year with Qatar -- a Gulf neighbor it had a rancorous split from in 2017.

At the same time, tensions have spiked between Saudi Arabia and another Gulf Cooperation Council neighbor, the United Arab Emirates, over differences on oil policy, geopolitical views and economic competition.

READ MORE: Politics Seep Into Oil as Diverging Goals Test Saudi-UAE Ties

“It’s almost a new crown prince who thinks about regional affairs differently,” Kamel said. “He’s much more interested in building a GCC-centric multifaceted relationship that does not rely only on one ally, which used to be the UAE, but builds on a much broader network of alliances.”

Relations between Oman and Saudi Arabia had long been cool despite their shared border. Saudi officials were wary of Oman’s cordial ties with Iran, while Omani officials cultivated a careful neutrality in a volatile region and were wary of undue influence from their larger neighbor.

But the death last year of Omani Sultan Qaboos bin Said, who ruled for five decades, opened an opportunity for change. The visit to Saudi Arabia was Sultan Haitham’s first trip abroad since he came to power.

Any sign of reticence was gone this weekend, as Saudi public figures shared effusive social media posts celebrating the alliance.

“The Omani-Saudi relations are set to scale new heights after Sunday, ushering in a new era of wider prosperity and expanded cooperation,” the Times of Oman said on Saturday.

(Updates with sultan arriving in first paragraph)

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