Iraqi Information Minister Mohammad Said al-Sahaf on Friday dismissed as "baseless" US claims that Syria was supplying Iraq with military equipment.
During an interview with Lebanese Al-Hayat LBC television, Al-Sahaf said US "accusations against brotherly Syria are of course baseless."
US Defense Secretary Donald H. Rumsfeld said at a Pentagon briefing on Friday that Syria was sending military equipment to Iraqi forces, warning his country would hold Syria accountable for the "hostile acts."
"We have information that shipments of military supplies have been crossing the border from Syria into Iraq, including night-vision goggles," he said.
Rumsfeld stressed the equipment "pose a threat to the allied troops and Syrian government should shoulder responsibility for that".
Al-Sahaf described Rumsfeld's accusation as "ridiculous" and said the US official "is lying every day".
Earlier, Washington has accused Russia of providing military equipment to Iraq.
The United States launched an anticipated war against Iraq on March 20, but their military advances in Iraq have been blocked by fierce resistance from the Iraqi army.