International Criminal Court prosecutors say the US may have tortured at least 88 people at a number of sites.

An International Criminal Court investigation of possible war crimes by US forces in Afghanistan is not “warranted or appropriate”, the US state department has said after prosecutors in The Hague found initial grounds for such a probe.

Elizabeth Trudeau, a state department spokeswoman, said on Tuesday that the US was not a party to the Rome Statute that created the ICC and had not consented to its jurisdiction.

She also said the US had a robust justice system able to deal with such complaints.

“The United States is deeply committed to complying with the law of war,” Trudeau said.

“We do not believe that an ICC examination or investigation with respect to actions of US personnel in relation to the situation in Afghanistan is warranted or appropriate.”

Inside the CIA’s torture programme

Her comments come a day after ICC prosecutors said in a report that there was “reasonable basis to believe” US forces had tortured at least 61 prisoners in Afghanistan and another 27 at CIA detention facilities elsewhere in 2003 and 2004.

The prosecutors’ office, headed by Fatou Bensouda, the ICC prosecutor, said it would decide imminently whether to pursue a full investigation.

The results could lead to charges being brought against individuals and the issuing of arrest warrants.

The US occupied Afghanistan in 2001 as it went after al-Qaeda leaders behind the September 11, 2001 attacks.

Crimes also may have been committed at US Central Intelligence Agency facilities in Poland, Lithuania and Romania, where some people captured in Afghanistan were taken, prosecutors said.

The US Justice Department, between 2009 and 2012, investigated CIA mistreatment of detainees; this included a full criminal investigation into two deaths in US custody. But ultimately it decided against prosecuting anyone.