Adam Boehler, the U.S. President’s Special Envoy for Hostage Affairs, has warned that Afghanistan could face consequences similar to those faced by Iran or Venezuela if American citizens detained in the country are not released.

The warning comes after U.S. Secretary of State Marco Rubio designated Afghanistan as a “state sponsor of wrongful detention” on Monday — a step that could lead to restrictions on the use of U.S. passports for travel to Afghanistan.

In a statement, Rubio called on Kabul to release all American citizens believed to be detained in the country, including Mahmood Habibi and Dennis Coyle.

Rubio accused the IEA of continuing to use what he described as “terrorist tactics,” including detaining individuals to extract ransom payments or political concessions. “These despicable tactics need to end,” he said.

According to a report by Reuters citing two informed sources, the United States is also seeking the return of the remains of writer Paul Overby, who was last seen in 2014 near the Durand Line.

The report said that if Afghanistan does not respond to Washington’s demands, the United States could restrict the use of American passports for travel to Afghanistan. Such restrictions are currently applied only to North Korea.

The move comes after the United States also designated Iran as a “state sponsor of wrongful detention” on February 26.

Rubio warned the U.S. could restrict travel to Iran over its detention of U.S. citizens, but has not imposed any restrictions. The U.S. and Israel launched a war against Iran ⁠the day after the determination was announced.

The Islamic Emirate has previously denied detaining Mahmood Habibi, the former head of Afghanistan’s Civil Aviation Authority.

It has released some U.S. prisoners following negotiations.