The relationship paid off: Iran provided Sudan with weaponry and expertise that allowed the country to set up a fairly extensive domestic arms industry, giving it the capability of building its own automatic weapons, rocket launchers, and even tanks.

The Sudanese regime lost many of it its Islamist trappings. The Islamic Movement changed its name to the National Congress Party (NCP) in the late 1990s and began evolving into a somewhat more conventional dictatorship in hopes of improving the country's economy and relations with the west.

But Sudan maintained close ties with Iran. International isolation over the government's conduct in wars in Darfur and South Sudan gave Sudan the added incentive to deepen ties with a fellow sanctioned regime. Iran and Sudan completed a military cooperation agreement in 2008, while the Sudanese military has deployed Iranian-built drones in both Darfur and the south of the country. The two governments were allies through 2014.

That began to change as the NCP began to faced steep financial crisis — and as Saudi Arabia began mobilizing the Sunni Arab states against Tehran.

(Reuters)
Sudanese President Omar Hassan al-Bashir (L) meets Iran's President Mahmoud Ahmadinejad during his arrival at Khartoum Airport September 25, 2011.

The NCP, which is still under international sanctions related to the Sudanese government's human rights abuses in Darfur, had faced a prolonged economic drought after the southern third of the country became the independent state of South Sudan in 2011. Khartoum and South Sudan failed to reach a durable compromise over the post-independence split of South Sudanese oil revenues (the oil's export is dependent on an oil transit infrastructure in the north of Sudan). Oil from the south had previously constituted nearly the entirety of Sudanese government revenue.

At the same time, the Middle East ignited. The escalating conflict in Syria sharpened the region's sectarian divisions, and events like the Yemeni civil war and the thaw in Iran-US relations heightened the competition between Riyadh and Tehran.

These tensions raised made a potentially swing state like Sudan even more important.

(Reuters)
Flames rise from Saudi Arabia's embassy during a demonstration in Tehran on January 2, 2016.

As Alberto Fernandez, current Vice President at the Middle East Media Research Institute and the Charge d'Affaires at the US embassy in Khartoum from 2007 to 2009 explained to Business Insider, amid both domestic and regional turmoil the increasingly pragmatic regime in Khartoum began to realize that its survival depended more on Saudi largess than on its relationship with Iran.

"These guys have been in power now for 26 years," Fernandez says of the NCP. "They're no longer the revolutionaries that they were. They're now a regime that wants to hold onto power. And in that sense they were fruit ripe for the plucking by the Saudis."

The thaw culminated in Sudan's March 2015 decision to join the Saudi-led anti-Houthi rebel coalition in Yemen, which is fighting to restore Yemen's internationally recognized government after an Iranian-supported Shi'ite militant movement deposed it in early 2015.

By that point, the NCP had determined that the Saudis had the unrivaled resources and willingness to secure the regime's long-term survival. "The Saudis can still outbid the Iranians," says Fernandez. "The Iranians have technical expertise and other things they can offer, but they're not swimming in cold hard cash the way the Saudis are."

(Emmanuel Pene/Agathocle de Syracuse/The Maghreb and Orient Courier)

The move has strategic implications for Iran. Sudan's partnership was more than just a symbolic victory for Iran, 0r a sign that the the Islamic Republic's state ideology was capable of resonating with Sunni Arab Islamists too. It also gave Iran a strategic way-point for weapons trafficking into both the Gaza Strip and Central and East Africa.

Sudan was a frequent staging area for Iranian weapons shipments heading north, to Hamas and Palestinian Islamic Jihad in Gaza. Sudan gave the Iranian arms industry, and the Iranian regime, access to regions of strategic and possibly commercial concern. Suspected Israeli attacks targeted Hamas weapons shipments or facilities in Sudan in 2009, 2011, and 2014. And as a 2012 study by Conflict Armaments Research detailed, Iranian munitions have been found throughout Africa, in places spanning from South Sudan to Cote D'Ivoire.

Iran also helped seed a Sudanese domestic weapons industry purported to be the third-largest in Africa, behind only Egypt and South Africa. According to a 2014 Small Arms Survey report, Iran owns a 35% stake in the Yarmouk industrial facility in Khartoum, which is believed to produce artillery, rocket launchers, and military-grade firearms.

Iran's Yamrouk investment hasn't been cost-free for the Sudanese regime: in October of 2012, the Israeli air force attacked the site, likely in order to destroy Iranian-supplied long-range rockets bound for Hamas in the Gaza Strip. Yarmouk was also cited in a 2006 US diplomatic cable published by WikiLeaks for its alleged connection to activities "that have the potential to contribute materially to WMD, missile, or certain other weapons programs in Iran or Syria."

As the Small Arms Survey recounts, Sudanese weapons factories produce a range of armaments, including light weaponry and small rocket launchers of Iranian design. Sudan has flown military drones of Iranian origin, and Patrick Megahan, a research associate for military affairs at the Foundation for Defense of Democracies, noted in an email to Business Insider that Sudan's state weapons enterprises had exhibited "a copy of an Iranian remote weapons station" at an international defense exhibition in Abu Dhabi in early 2015.

Emile Lebrun, the editor of the Small Arms Survey's Human Security Baseline Assessment for Sudan and South Sudan, speculates that Iranian assistance "was already very limited before the Yemen campaign was underway."

But it's still "unclear," he wrote to Business Insider in an email, "whether the Iranian technicians working in the Sudanese arms factories (some hundreds of workers, according to reports) can be replaced with local specialists."

(AP)
In this Friday, Jan. 23, 2015, file photo released by the Saudi Press Agency, King Salman bin Abdul-Aziz Al Saud makes his first speech as king following the death of King Abdullah.

Sudan's value as a strategic asset to Iran, and Iran's role in helping Sudan establish a domestic arms production capability, suggest that the relationship between the two countries may continue in some more muted, sub-official form. There might be some enduring (if informal) cooperation between officials from the two countries regarding weapons trafficking or continued Iranian involvement in the arms sector.

"My sense is that we're going to see Sudan inch away from Iran but Iran will maintain lingering assets in the country whether Sudan likes it or not," says Jonathan Schanzer, vice president of research at the Foundation for Defense of Democracies.

But on the geopolitical level, Saudi Arabia was able to ply away Iran's only Sunni Arab ally — a country that enjoyed longstanding military and strategic ties with Tehran.

"It looks like the Saudis have outmaneuvered the Iranians," Schanzer told Business Insider. "They pulled a proxy out from under Iran's wing."

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