Mr Darwish worked in Maryland at the time of the alleged conspiracy
An Iraqi-born Canadian has been charged by the US authorities with conspiring to spy for the Iraqi government of Saddam Hussein from 2000 until 2003.
Mouyad Mahmoud Darwish, 47, who worked in the US at the time, is accused of giving information to Iraqi officials.
He was detained on 24 December as he tried to enter the US from Canada.
Mr Darwish and another man charged last week are among at least 16 people accused by the US since 2003 of acting as illegal agents of Saddam Hussein.
Mr Darwish and Saubhe Jassim Al-Dellemy are accused of conspiring to act as unregistered agents of a foreign government, which carries a maximum prison term of five years.
Mr Dellemy, an Iraqi national who lives in Maryland, pleaded guilty to the same charge in a federal court last week.
The pair are not accused of seeking or obtaining classified information.
A criminal complaint filed by the US justice department alleges that Mr Darwish was paid to give information to Iraqi government and intelligence officials.
Among the information he allegedly passed on before the 2003 US invasion of Iraq was that Iraqi volunteers were being trained in Virginia, according to the complaint.
Mr Darwish worked in Maryland at the time of the alleged conspiracy as a restaurant cook and also as a driver at the Iraqi embassy in Washington.
The US authorities learned of his alleged activities through Iraqi intelligence service documents seized by US troops after the 2003 invasion of Iraq.