Sudan pushed back against Iranian influence reach Tuesday, announcing the closure of Tehran-backed cultural centers and ordering the expulsion of a diplomat and other envoys in an apparent sign of fraying ties after years of close cooperation.

The decision suggests that Sudan’s Sunni leadership increasingly is worried about the influence exerted by Shiite-dominated Iran. It also could signal wider complications for Iran, which has used Sudan’s main Red Sea port as an important naval foothold in the region and has sought to expand military bonds.

Western-backed Persian Gulf nations, led by Saudi Arabia, have been highly critical of Iran’s growing presence in Sudan. Meanwhile, the government of President Omar Hassan al-Bashir has appealed to Saudi Arabia and other Gulf states for aid and investment to counter Western sanctions over the conflict in Sudan’s Darfur region.

Sudan’s slap against Iran mentioned only Iranian cultural sites and staff members, who often serve in direct or sideline diplomatic roles. It’s unclear whether the tensions will spill over to military affairs.

Iran is among Sudan’s arms suppliers, and Iranian warships have called at Port Sudan as part of Iran’s efforts to expand its naval profile in the region, including trips through the Suez Canal. Iran also has been accused of using Sudan as a route to supply Hamas in the Gaza Strip.

In 2012, Sudan claimed that Israel was behind blasts that damaged a weapons factory.

In a statement, Youssef al-Kordofani, Sudan’s Foreign Ministry spokesman, said that immediate closure was ordered for Iran’s cultural centers, including the main site in the capital, Khartoum. The cultural attache and other staff members were given 72 hours to leave the country.

The statement, carried by Sudan’s official news agency, appeared aimed at fears of expanding Iranian influence, saying the Khartoum center had “become threatening to Sudan’s social and ideological security.’’