The International Criminal Court on Tuesday said its work would continue "undeterred" after Washington threatened to prosecute its officials if Americans are charged with war crimes committed in Afghanistan.

"The ICC, as a court of law, will continue to do its work undeterred, in accordance with those principles and the overarching idea of the rule of law," the tribunal said in a statement.

The Hague-based court's response comes a day after the United States threatened to arrest and sanction court officials should they move to charge any American who served in Afghanistan with war crimes.

White House National Security Advisor John Bolton called the Hague-based rights body "unaccountable" and "outright dangerous" to the United States, Israel and other allies, and said any probe of US service members would be "an utterly unfounded, unjustifiable investigation".

"If the court comes after us, Israel or other US allies, we will not sit quietly," Bolton said.

The US was prepared to slap financial sanctions and criminal charges on officials of the court if they proceed against any Americans, he added.

But in response, the ICC declared itself an "independent and impartial judicial institution".

It also stressed that it would only investigate and prosecute crimes when the states will not or can not do so.

The Hague-based ICC was set up in 2002 with jurisdiction to investigate and prosecute the world's worst crimes including genocide, war crimes and crimes against humanity.

The court however does not have the capacity to arrest suspects and depends on member states for their cooperation.

The United States has not signed up to the court and in 2002 Congress passed a law enabling Washington to invade the Netherlands to liberate any US citizen held by the court.

In this Monday, Sept. 10, 2018 file photo, National Security Adviser John Bolton speaks at a Federalist Society luncheon at the Mayflower Hotel, in Washington. Afghan rights workers are warning that Bolton's blistering attack on the International Criminal Court investigating war crimes allegations will strengthen a climate of impunity in Afghanistan, prolong the war and embolden those carrying out acts of violence. (AP)