WASHINGTON, DC - The volatile White House is under siege again as firebrand National Security Advisor John Bolton has been shown the door.

President Donald Trump says he has fired Bolton.

"I informed John Bolton last night that his services are no longer needed at the White House. I disagreed strongly with many of his suggestions, as did others in the Administration," Trump announced on his Twitter page on Tuesday.

It was news to Bolton who fired back on Twitter with a post saying: "I offered to resign last night and President Trump said, 'Let's talk about it tomorrow.'"

Trump astonishingly said he would name a replacement next week.

Bolton, one of the main architects of the Iraq War, a fierce advocate for Israel, and a hardline opponent of North Korea, Iran and Russia, is believed to have been behind the breakdown in talks with North Korea, and has played a dominant hand in relations with Iran which have led nowhere.

It is believed the president and his security advisor had a heated argument on Monday night.

Bolton, who is 70 years of age, is the third National Security Advisor in the Trump administration. He took up the role in April last year after first canvassing the secretary of state job. He was a contributor to the Fox News Channel prior to that. He served as the U.S. Ambassador to the United Nations for President `George W. Bush for a period but did not continue as the U.S. Senate refused to endorse his nomination. Prior to that he was the Under Secretary of State for Arms Control and International Security Affairs, appointed to that role by President George W. Bush.

Bolton and current secretary Mike Pompeo are believed to have crossed swords on a number of occasions.

"I don't think that any leader around the world should make any assumption that because some one of us departs that President Trump's foreign policy will change in a material way," Pompeo said Tuesday.