President Mr George W. Bush will this evening present his arguments for war against Iraq in a televised address.
Over the weekend, Mr Bush warned Iraqi President Saddam Hussein must be disarmed before he could inflict "massive and sudden horror" on America.
The Iraqi leader had a "horrible history" of attacking his enemies first, Mr Bush told hundreds of police and National Guardsmen in New Hampshire. "We cannot ignore history, we must not ignore reality. We must do everything we can to disarm this man before he hurts one single American".
The President's address to the nation comes as the administration steps up pressure on Congress and the United Nations for authority to use force against Baghdad.
In his weekly radio address, Mr Bush appealed to listeners to call their members of Congress to pass a resolution giving him authority to use force against Iraq to help persuade members of the UN Security Council to back a tough new resolution.
The Washington Postreported yesterday that US intelligence officials believe the US military build-up against Iraq would encourage Iraqi army officers to stage a coup against Saddam rather than face death in a fight against superior military technology.