The countries had been asked to supply legal experts to join a team of up to 50 American lawyers, investigators and prosecutors who began leaving for Iraq at the weekend.
The group – to be called the Regime Crimes Adviser’s Office – will report to the Coalition Provisional Authority headed by US administrator Paul Bremer.
A US Justice Department official said investigators wanted to lay the groundwork for war crimes cases against Saddam and others that would eventually be turned over to Iraqi prosecutors.