'The only way to avoid serious consequences built into (UN Security Council Resolution) 1441 is for Saddam Hussein and his immediate cohorts to leave and country and allow the issue to be resolved by the peaceful use of force,' he said. Powell said that the US, Spain and the UK had decided not to call for a vote on the second resolution circulated to the UN last month. We spent a great deal of time overnight talking to friends and colleagues around the world,' Powell said. 'It was our decision that no further purpose would be served by pushing this resolution.'

Powell said that possible future action was authorised by UN Security Council resolutions 678 of 1990, 687 of 1991 and 1441, approved last November. 'We believe our actions are supported by international law,' he said.

President Bush is to address the American people at 0100 GMT on 18 March. Powell said that Bush would issue an ultimatum for Saddam Hussein to leave Iraq.