(CNN) On Thursday morning, President Donald Trump tweeted this: "Not that it matters but I never fired James Comey because of Russia! The Corrupt Mainstream Media loves to keep pushing that narrative, but they know it is not true!"

Some claims Trump makes are hard to fact check because they rely on subjective measures or are open for interpretation.

This is not one of those.

Let me take you back to early May 2017. In the early afternoon of May 9, Trump fires then-FBI Director James Comey.

The following day -- May 10 -- Trump meets with Russian Defense Minister Sergey Lavrov and then-Russian Ambassador to the US Sergey Kislyak . In that Oval Office huddle, Trump tells the two Russians this, according to The New York Times: "I just fired the head of the FBI. He was crazy, a real nut job,I faced great pressure because of Russia. That's taken off."

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