Cindy Saine at the State Department and Margaret Besheer at the United Nations contributed to this report.

The United States has revoked the visa of the chief prosecutor of the International Criminal Court, Fatou Bensouda, over a possible investigation of U.S. soldiers’ actions in Afghanistan.

Bensouda’s office said Friday that U.S. authorities revoked the prosecutor’s visa for entry into the United States, and a U.S. State Department spokesperson confirmed the action.

The spokesperson said Friday, “The United States will take the necessary steps to protect its sovereignty and to protect our people from unjust investigation and prosecution by the International Criminal Court [ICC].”

U.S. Secretary of State Mike Pompeo said last month that the United States would revoke or deny visas to ICC staff investigating possible war crimes by U.S. forces.

The United States in not a member of the ICC, along with Russia and China.

Bensouda’s office said that Bensouda, a Gambian national, would exercise her duties as ICC prosecutor “without fear or favor.”

It said the U.S. decision was not expected to impact Bensouda’s travels to the United Nations in New York where she gives regular briefings to the U.N. Security Council.

U.N. spokesman Stephane Dujarric said: “We very much hope [the United States] will honor the agreement” for ICC staff members to travel to the United Nations. 

Bensouda is expected to brief the U.N. Security Council next month about her investigations in Libya. 

ICC judges have been reviewing materials on possible war crimes committed by U.S. soldiers in Afghanistan, but have yet to make a decision on whether to open a formal investigation into the matter.

The ICC, located in The Hague, prosecutes crimes only when other nations are unwilling or unable to bring suspects to justice.