According to The New York Times, former FBI Director James B. Comey, who was summarily fired by President Trump last week, then declined to  testify before the Senate Intelligence Committee on Tuesday in closed-door testimony, is actually willing to testify, but wants it to be in public.

Comey’s reported willingness to testify in public would be a direct challenge to Trump, who warned Comey against leaking anything negative about him on Friday, tweeting;

Trump’s tweet, which may have been prompted by an article in the Times that reported he had asked Comey to pledge loyalty during a dinner at the White House, stirred up controversy in Washington D.C. as it hinted Trump may have taped the conversation he had with Comey, although Trump later refused to say confirm whether he tapes people who have visited him. Asked by Fox News whether he had taped conversations. Trump answered, “That I can’t talk about. I won’t talk about it. All I want is for Comey to be honest.”

The timeline of events leading up to the report that Comey wants to testify publicly looks like this:

1. Trump fires Comey last Tuesday, indicating that that the firing was triggered by letters from Attorney General Jeff Sessions and Deputy Attorney General Rod J. Rosenstein, and was driven by Comey’s refusal last summer to prosecute Hillary Clinton for her email misconduct.  Trump writes of Rosenstein and Sessions that he “accepted their recommendation.” This version of events is corroborated by Sean Spicer, the White House press secretary, on Tuesday night and Vice-President Mike Pence on Wednesday. As FBI director, Comey reported to Rosenstein.

2. Reports surface on Thursday that Rosenstein threatens to quit because Trump cited his letter as the reason for firing Comey.

3. On Thursday, Trump changes the story; he tells Lester Holt in an interview with NBC News that he had already decided to fire Comey because of the investigation Comey was heading into possible collusion between Russia and the Trump campaign. Trump states, “And in fact, when I decided to just do it, I said to myself, I said, ‘You know, this Russia thing with Trump and Russia is a made-up story. It’s an excuse by the Democrats for having lost an election that they should have won.’” Trump says Comey asked for a dinner because he wanted to be reassured that he was keeping his job. Trump states, “He wanted to stay on as the F.B.I. head. I said: ‘I’ll consider. We’ll see what happens.’ But we had a very nice dinner and at that time, he told me I wasn’t under investigation, which I knew anyway.” Trump says he had two subsequent phone conversations wioth Comey, who reassured him that he was not under investigation.

4. On Friday, Trump explains the mixed messages sent out by himself and his spokespeople by tweeting, “As a very active President with lots of things happening, it is not possible for my surrogates to stand at podium with perfect accuracy!”

Trump’s threat to Comey is not the first time he has threatened those opposing him; he threatened Senator Ted Cruz during the presidential primaries, tweeting:

He later threatened MSNBC hosts Joe Scarborough and Mika Brzezinski after they criticized him:

Threatening Comey, though, could have much harsher consequences; Samuel W. Buell, a former federal prosecutor, told the Times that Trump’s threat could be interpreted as an obstruction of justice because it could be viewed as an effort to intimidate a witness to any future investigation. Buell added, "If this were an actual criminal investigation — in other words, if there were a prosecutor and a defense lawyer in the picture — this would draw a severe phone call to counsel warning that the defendant is at serious risk of indictment if he continues to speak to witnesses."