AFP News reports that while addressing reporters before leaving on a trip to California, Trump spoke openly of his disagreements with Tillerson - including over the Iran nuclear deal - as he explained his decision to replace him.
Mr Tillerson also won few plaudits from career diplomats for his performance at the State Department.
"We got along actually quite well but we disagreed on things", Trump said on the White House lawn on Tuesday.
Trump said he will nominate CIA Director Mike Pompeo to replace the former Exxon Mobil chief executive and Deputy CIA Director Gina Haspel to run the spy agency.
If formally nominated and confirmed, Pompeo will be the first former Central Intelligence Agency director to become secretary of state.
The biggest shakeup of Mr Trump's cabinet since he took office in January 2017 was announced by the president on Twitter as his administration prepares for an unprecedented meeting with the leader of North Korea. "When you look at the Iran deal - I think it's awful. Congratulations to all!" Trump tweeted. As the president consistently poked the dictatorial bear through vague threats of military response and elementary school-level nicknames, Tillerson continued to float the importance of nuanced diplomatic efforts in order to avoid any escalation between the two nations as each flexed its nuclear muscles.
Goldstein added in his statement that Tillerson is "unaware of the reason" he's been removed but said he is "grateful for the opportunity to serve, and still believes strongly that public service is a noble calling".
While some intelligence officers have said that Pompeo tends to tell Trump what he wants to hear rather than giving him their assessments, others say they have been impressed by his intellect, willingness to listen and advocacy of more robust covert operations.
According to the Washington Post, Trump asked Tillerson to step aside last Friday.
Mr. Trump said Mr. Pompeo "has earned the praise of members in both parties by strengthening our intelligence gathering, modernizing our defensive and offensive capabilities, and building close ties with our friends and allies in the worldwide intelligence community", the president said in a statement. "I wish him all the best in his future endeavors". He's about to meet with North Korea, the Russian threat continues to pervade the globe, and key ambassadorships go empty.
Tillerson, like most in the administration, seemed to be blindsided by Trump's acceptance of a meeting with the North Korean dictator. Paid $27.3 million past year, Tillerson has accumulated roughly $160 million in Exxon stock along with $149 million of unvested stock options, according a proxy statement the company filed with the Securities and Exchange Commission.
Senior Trump administration officials also made it known in November that the White House had drafted a plan to replace Mr Tillerson.
Tillerson's departure marks the latest in a flood of turnover in Trump's inner circle, including the exits of national security advisor Mike Flynn, strategist Steve Bannon, chief of staff Reince Priebus, top economic advisor Gary Cohn, Secretary of Health and Human Services Tom Price, and White House communications director Hope Hicks.
The president called her by her first name Tuesday morning in comments to reporters, and praised her.
The Federation Council's International Affairs Committee deputy chairman Vladimir Dzhabarov said that Pompeo "may have the chance to become a man who will stop our relations from dropping rock-bottom", the RBC business portal reported.