Asked how Tillerson learned of his dismissal, Trump said Tuesday that "Rex and I have been talking about this a long time".
Despite his signature catchphrase, Trump often lets others in the White House do his dirty work or pushes out subordinates by tweet or through public shaming.
Once Pompeo becomes secretary of state after his expected confirmation by the Senate, he will surely diminish the chances that President Trump might get carried away with the spotlight of a high-profile summit with Kim.
While Murphy argued that Pompeo's record against diplomacy bodes ill for the United States' top diplomat, he questioned how effective an advocate Tillerson had been for keeping the United States in the deal. Pompeo will need confirmation by the Senate.
White House officials said Kelly told Tillerson that Trump wanted a change and he should step down.
Torture has since been explicitly outlawed by the government, and despite Trump's endorsement of it, there have been no reports of the U.S. intelligence agencies returning to the practice. Trump has named Mike Pompeo, the director of the CIA, as his next pick to lead the State Department, with Deputy Director Gina Haspel slated to lead the agency. "However, my understanding is he doesn't want the deal to disappear", said a former senior US official.
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Our understanding is that the disagreement had something to do with North Korea issues, or just a general accumulation of disagreements.
The plans to oust Tillerson had been drawn up months ago, but the timing caught even senior White House officials unawares. Gary Cohn recently announced his resignation as director of the National Economic Council. Tillerson will be "much happier now", Trump said.
Prior to Tillerson's visit, reports in the USA media had indicated tension between the president and his secretary.
Mr Trump and Mr Tillerson had clashed on a number of policy issues, with the former secretary of state critical of the decision to pull out of the Paris climate accord and of the Trump administration's rejection of the Iran nuclear deal. John McEntee was one of many White House officials yet to receive permanent security clearance because they could not pass Federal Bureau of Investigation background checks.
Tillerson was reported to have privately called Trump a "moron" in July after the president suggested a 10-fold increase in the USA nuclear arsenal. This is bad news for the country and the world.
Pompeo is also likely to also oppose the commercial illogic of the Iran nuclear agreement, which enriches the Islamic clerics who rule the nation for their nuclear restraint and then allows them to use billions of dollars to underwrite their aggressive regional ambitions.
Many Democrats in Congress expressed dismay at the firing, which they said would sow more instability in the Trump administration at a crucial time.
I was not surprised by the news this morning that he was out as Secretary of State. An appointment for the ambassador to South Korea fell apart at the last minute. This week, he told Fox News that "never before have we had the North Koreans in a position where their economy was at such risk, where their leadership was under such pressure".
If, as now appears likely, Trump indeed decides to drop out of the Joint Comprehensive Plan of Action (JCPOA), then the deal - and the hopes of a generation of European and USA diplomats - will be dead.