The US has threatened sanctions against the International Criminal Court if it goes ahead with prosecutions against Americans.
The court is currently considering prosecuting US servicemen over alleged detainee abuse in Afghanistan.
National Security Adviser John Bolton called the court "illegitimate" and vowed the US would do everything "to protect our citizens".
The US is among dozens of nations not to have joined the 2002-founded court.
"The United States will use any means necessary to protect our citizens and those of our allies from unjust prosecution by this illegitimate court," White House National Security Adviser John Bolton Bolton said in a speech Monday to the conservative Federalist Society.
The ICC has long been controversial, with critics like Bolton suggesting it's a threat to American sovereignty. Supporters say the international court, based in the Netherlands, offers recourse for victims of genocide and other war crimes in lawless countries.
Bolton blasted the ICC as a “supranational tribunal" that claims "unfettered discretion to investigate, charge, and prosecute individuals, regardless of whether their countries have acceded to the Rome Statute." The US is not a signatory to the Rome agreement.
"In theory, the ICC holds perpetrators of the most egregious atrocities accountable for their crimes, provides justice to the victims, and deters future abuses,” Bolton told a receptive audience of Federal Society members. “In practice, however, the court has been ineffective, unaccountable, and indeed, outright dangerous.”
USA Today, BBC Online
BDST: 1014 HRS, SEPT 11, 2018