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The role of the nuclear pact

Bilateral relations were severed in January 2016, after regime militiamen stormed the Saudi embassy in Tehran. Amirabdollahian was then the deputy foreign minister for Arab affairs. In 2019, he told the website Iranian Diplomacy that Saudi Arabia had taken measures vis-a-vis Iran's nuclear pact with the world powers.

It's unlikely Ali Khamenei will tolerate the Saudi kingdom's rising power in the region.

He said "the Saudis' insane conduct toward [the pact] led them to conclude that they must prevent [its implementation] in a peaceful environment ... I think the Saudis are quite deluded, and their delusion consists in thinking that Trump is an opportunity for them to place themselves on the path of conflict with the Islamic Republic while relying on Trump." He meant the administration led by the U.S. President Donald J.Trump, which was hostile to Iran's regime. This, he said, "is not how we view Saudi Arabia. I think Yemen should have been a big lesson for the Saudis."

The minister was effectively admitting the Houthis were the Islamic Republic's tool for getting back at Saudi Arabia.

Yet in the past two years, both sides have taken steps to improve relations, without firm results as yet. Nor is the situation likely to change this time.

Riyadh's warming relations with Israel

Iran's former ambassador in Lebanon, Ahmad Dastmalchian, told the ILNA news agency in Tehran that Saudi Arabia is doing Israel's bidding in the region, and has "entrusted its national security, and life and death to Tel Aviv." Riyadh, he said, had been financing a good many "security and political projects in the region," or acting as a "logistical supplier."

The United States, said Dastmalchian, has "in turn tried to provide intelligence and security backing, while Israel has simply followed its own interests in all this."

Furthermore, it seems unlikely Iran's Supreme Leader Ali Khamenei will tolerate, even in this weak period of his leadership, the kingdom's rising power in the region and beyond, and especially its financial clout. He is usually disparaging when he speaks of Riyadh's princely rulers. In 2017, he compared them to "dairy cows," saying, "the idiots think that by giving money and aid, they can attract the goodwill of Islam's enemies."

Iranian regime officials are hopeful of moving toward better diplomatic ties and a reopening of embassies. Yet the balance of power between the sides began to change in Riyadh's favor years ago. For the kingdom's power has shifted from relying mostly on arms, to economic and political clout. The countries might have had peaceful relations before in considerably quieter, and more equitable, conditions than today's acute clash of interests.

If nuclear talks break down, Iran's regime may become more aggressive.

Beyond this, the Abraham Accord or reconciliation of Arab states and Israel has been possible thanks to the green light that the Saudis gave their regional partners, and it is a considerable political and ideological defeat for the Islamic Republic.

Assuming all Houthis follow Tehran's instructions — and they may not — improved ties may curb attacks on Saudi interests and aid its economy. Tehran will also benefit from no longer having to support them. Unlike Iran's regime, the Saudis are not pressed for cash or resources and could even offer the Houthis a better deal. Presently, they may consider it more convenient to keep the softer approach toward Tehran.

For if nuclear talks with the West break down, Iran's regime may become more aggressive, and as experience has shown, tensions often prompt a renewal of missile or drone attacks on the Saudis, on tankers and on foreign shipping. Riyadh must have a way of keeping the Tehran regime quiet, in a distinctly unquiet time.