"If you're responsible for the proposed ICC investigation of US personnel in connection with the situation in Afghanistan you should not assume that you still have, or will get, a visa or that you will permitted to enter in the US," Secretary of State Mike Pompeo told reporters.

Pompeo told a news conference in Washington the first visa denials had already been issued under the new regime but gave no idea of how many people might be targeted in total.

In November 2017, ICC prosecutor Fatou Bensouda announced that she would ask judges for permission to open an investigation into alleged war crimes committed in the Afghan conflict, including by the US military.

In an unprecedented attack on the global body, charged with judging war crimes and crimes against humanity, the White House threatened its judges or prosecutors in September last year with sanctions if they target Americans or Israel.

Pompeo said the new visa restrictions would include "persons who take or have taken action to request or further such an investigation."

"These visa restrictions may also be used to deter ICC efforts to pursue allies' personnel, including Israelis," the secretary of state added.