British Defence Secretary Mr Geoff Hoon today announced the call-up of more reservists ahead of a possible war in Iraq.
The British Ministry of Defence has already announced plans to mobilise 1,500 part-time soldiers, sailors and airmen.
In a written ministerial statement, Mr Hoon said that a further 4,500 were likely to be needed.
The announcement came as the British Prime Minister Mr Tony Blair told the Cabinet there was a final opportunity for Saddam Hussein to comply with United Nations resolution 1441.
"There is a window of opportunity for Saddam Hussein to comply with the obligations," Mr Blair's official spokesman said. "But every day that passes that window gets narrower.
"The choice is still Saddam Hussein's. It is not going to be his choice forever if he continues to defy the will of the international community," he said.
PA