The United States is revoking visas for South Sudanese passport holders because the country’s transitional government has not accepted citizens who were expelled from the U.S., according to the Secretary of State Marco Rubio. 

“As South Sudan’s transitional government has failed to fully respect this principle, effective immediately, the United States Department of State is taking actions to revoke all visas held by South Sudanese passport holders and prevent further issuance to prevent entry into the United States by South Sudanese passport holders,” Rubio said in a statement released Saturday. 

Rubio added that the U.S. government will be “prepared to review these actions when South Sudan is in full cooperation.” 

The U.S.’s top diplomat accused South Sudan’s government of “taking advantage of the United States.”  

“Enforcing our nation’s immigration laws is critically important to the national security and public safety of the United States,” Rubio said. “Every country must accept the return of its citizens in a timely manner when another country, including the United States, seeks to remove them.” 

Apart from canceling visas of South Sudanese citizens, Rubio said the U.S. is restricting any “further issuance to prevent entry into the United States, effective immediately.” 

The sweeping action to revoke visas of passport holders of a specific nation was the first since President Trump started his second White House term on Jan. 20. 

South Africa, positioned in East Africa, is one of the world’s poorest and newest countries in the world, having declared independence in July 2011. 

Tension has been rising in South Sudan in recent weeks. 

The United Nations’ Secretary-General António Guterres warned late last month that South Sudan was falling into a deeper crisis and called on regional and international leaders to help the country avert a civil war. 

“South Sudan may have fallen off the world’s radar,” Guterres said on March 28. “But we cannot let the situation fall over the abyss.”

The State Department last month ordered all non-emergency U.S. government personnel to depart South Sudan due to “continued security threats.”