Washington, June 18 (Reuters): President George W. Bush today rejected calls for a withdrawal of US troops from Iraq and tried to counter growing impatience with the war by calling it a “vital test” for American security.

“The mission isn’t easy, and it will not be accomplished overnight,” Bush said.

Coming under renewed attack for his rationale for invading Iraq in March 2003, Bush described the conflict as part of the broader US war on terrorism. He said stabilising Iraq was important for American interests.