WASHINGTON — President Donald Trump has removed U.S. Secretary of State Rex Tillerson, a native Texan, from his Cabinet post, replacing him with CIA Director Mike Pompeo.

The president made the move on Friday, according to The Washington Post, and in a public statement said "a great deal has been accomplished over the last 14 months" of Tillerson's tenure. 

But other details emerged Tuesday that conflicted with that account, including an NBC report suggesting Tillerson found out he was fired from the president's tweets. 

The latter scenario would indicate that Tillerson's termination came after he took a hard line supporting British allegations that Russian operatives poisoned an ex-Russian spy and his daughter. Trump has been hesitant to criticize Russia, even as special counsel Robert Mueller investigates whether the Trump campaign colluded with Russia in the 2016 presidential election. 

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When speaking to reporters on Tuesday, Trump indicated the Tillerson decision had long been on his mind and said the two "disagreed on things" and "were not thinking the same." But he said he still hoped to maintain a relationship with Tillerson.  

"I actually got on well with Rex," he said, "but it was a different mindset."

In the afternoon, Tillerson told reporters at the State Department that he will leave his role in the federal government on March 31.

“Between now and then, I will address a few administrative matters related to my departure and work towards a smooth and orderly transition for Secretary of State-Designate Mike Pompeo,” Tillerson said. 

He went on to remind his department's "foreign service officers and civil service colleagues" that they are all bound by a commitment "to support and defend the Constitution.”

“As a state department we are bound together by that oath, we remain steadfast here in Washington and at post across the world," Tillerson said. “These are experiences no lecture hall in an academic environment or in a think tank can teach you. Only by people going to the front lines to serve can they develop this kind of talent.”

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The news follows a year of escalating tensions between Tillerson and Trump, including reports in October that Tillerson called Trump "a moron."

The change at the State Department comes at a consequential moment in American foreign policy: Trump agreed last week to meet with North Korean leader Kim Jong-un.

A series of senior Trump administration officials have left the administration in recent months, a remarkable level of churn so early in a presidential term. 

Tillerson leaves behind a State Department that is widely viewed as understaffed, strapped for resources and demoralized due to pushes for budget cuts by the Trump administration. 

A Wichita Falls native, Tillerson was a surprise choice for the secretary of state position but had the backing of much of the Republican foreign policy establishment. He had no diplomatic experience but was the longtime CEO of ExxonMobil. 

Tillerson is closely aligned with a fellow Texan, NATO Ambassador Kay Bailey Hutchison.

During his remarks to reporters Tuesday, Tillerson did not specifically thank Trump for the opportunity to serve as the nation's top diplomat.

“All of us we know want to leave this place as a better place for the next generation," Tillerson said. "I’ll now return to private life to private citizen as a proud American, proud of the opportunity I’ve had to serve my country."

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Speaking with reporters in Washington after the news broke, U.S. Sen. Ted Cruz, R-Texas, said he was "grateful for the good and hard work that Rex has provided as secretary of state, and I’m confident that Mike Pompeo will make an excellent secretary of state.” Yet Cruz also alluded to the rocky relationship between Tillerson and Trump.

"These are challenging times,” Cruz said. "It was evident for some time that Secretary Tillerson and the president — that there was real tension between the two of them. And that’s a difficult situation in any administration, to have the secretary of state and the president on different pages." 

Rishika Dugyala and Patrick Svitek contributed to this report.

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