Strongly disagreed with many of his suggestions, as did others in the administration, the U.S. President said in a tweet.

U.S. National Security Adviser John Bolton, considered the most hawkish among senior Trump administration officials, left his post on Tuesday.

Mr. Bolton, the third National Security Adviser in the current administration, had a long list of differences with U.S. President Donald Trump on a range of security and foreign policy issues — including Iran, North Korea and Afghanistan, leading to his departure around midday on Tuesday.

“I informed John Bolton last night that his services are no longer needed at the White House,” Mr. Trump said in a tweet.

“I disagreed strongly with many of his suggestions, as did others in the Administration, and therefore I asked John for his resignation, which was given to me this morning. I thank John very much for his service,” he said, adding that he would name a new NSA next week.

‘Different versions’

Mr Bolton’s account of his departure differed from that of his former boss.

“I offered to resign last night and President Trump said, ‘Let’s talk about it tomorrow,” read a tweet from Mr. Bolton, that followed Mr Trump’s tweet.

“I will have my say in due course. But I have given you the facts on the resignation. My sole concern is U.S. national security,” Mr. Bolton is reported as saying in the Washington Post.

The differences between the two were known before Mr. Bolton took on the job in April 2018, with Mr. Bolton, an erstwhile UN Ambassador, taking a trademark hawkish approach to foreign policy in contrast to Mr. Trump’s isolationist and non-interventionist approach. One month prior to joining the administration, Mr. Bolton, who is a declared proponent of regime change in Iran, wrote an op-ed calling for a pre-emptive strike on the country. Shortly after he took over as NSA, the U.S. withdrew from the Joint Comprehensive Plan of Action (JCPOA), the international deal to limit Iran’s nuclear programme. More recently, Mr. Bolton did not reportedly support direct talks between Mr. Trump and Iranian President Hassan Rouhani.

On North Korea, Mr. Bolton did not reportedly approve of the bonhomie between the regime’s leader Kim Jung-un and Mr. Trump, and on Russia, Mr. Bolton reportedly did not support Mr. Trump’s repeated calls for Russia to rejoin the G-7.

Last week, the differences between Mr. Trump and his NSA came to the surface once more. The two men were at odds with each other on a settlement the U.S. was finalising with the Taliban and Mr. Bolton reportedly worked on Mr. Trump to stop him from closing the deal. Mr. Trump said on Monday that he had called off a last minute gathering at Camp David with the Taliban and Afghan President Ashraf Ghani after the Taliban claimed responsibility for an attack that killed 12 people, including an American soldier.

Approximately an hour before news of Mr. Bolton’s departure broke, the White House Press Office had said that Mr. Bolton, Secretary of State Mike Pompeo and Treasury Secretary Steve Mnuchin would address a joint press briefing, suggesting that Mr. Bolton’s departure was not anticipated. A White House official said that Mr. Bolton had left the White House after Mr. Trump’s tweet and would not attend the press briefing, the Associated Press reported.

Mr. Pompeo and Mr. Mnuchin addressed the press on strengthening counter-terrorism designations, but ended up taking questions on their Mr Bolton’s departure.

“I’m never surprised, and I don’t mean that on just this issue,” Mr. Pompeo said when asked if he was surprised by Mr. Bolton’s departure.

The Secretary of State had significant differences with Mr. Bolton, and he alluded to these during the press briefing.

Mr. Bolton’s departure could see an easing of tensions between the U.S. and Iran.

Asked if Mr. Trump could meet Mr. Rouhani at the United Nations General Assembly later this month, Mr. Pompeo replied, “Sure.”