Special counsel Robert Mueller's investigation is potentially heating up, with two sources revealing to the Washington Post that Mueller wants to question President Donald Trump about "his decisions to oust national security adviser Michael Flynn and FBI Director James B. Comey."

According to the Post, the development indicates Mueller's probe may be "intensifying its focus on possible efforts by the president or others to obstruct or blunt the special counsel's probe."

Trump's legal team, the newspaper reports, has "crafted some negotiating terms for the president's interview" and "hopes to provide Trump's testimony in a hybrid form—answering some questions in a face-to-face interview and others in a written statement."

While the president has reportedly told his lawyers that he isn't worried about an interview, the Post notes that "some of Trump's close advisers and friends fear a face-to-face interview with Mueller could put the president in legal jeopardy," due to "Trump's lack of precision in his speech and his penchant for hyperbole."

The news comes on the heels of reports that Attorney General Jeff Sessions was questioned "for several hours" by Mueller's investigators last week, the first time the special counsel's team is known to have interviewed a member of Trump's cabinet. Those reports were quickly followed by the revelation that Comey spoke to Meuller's team last year.

In a "Nixonian" move that critics said "should send a chill down the spine of every American," Trump fired Comey in May amid the FBI's investigation into Russian meddling in the 2016 election. Flynn, who resigned in February, has admitted he lied to the FBI about his contacts with the Russian ambassador to the United States Sergey Kislyak and is reportedly cooperating with the investigation.

In March, Sessions recused himself from all investigations into alleged election meddling by Russians after it was revealed that during his confirmation hearing to lead the Justice Department, Sessions declined to mention campaign season meetings with Kislyak.