The official word from Donald Trump’s lawyers is that they are fully cooperating with special counsel Robert Mueller’s investigation into Trump’s Russia ties. And it was virtually inevitable that Mueller would want to talk to White House aides. But in a sign that Mueller is moving decisively—a sign that’s likely to enrage Trump once again—his team is “in talks with the West Wing about interviewing current and former senior administration officials,” Michael Schmidt, Matt Apuzzo, and Maggie Haberman report for the New York Times:

Mr. Mueller has asked the White House about specific meetings, who attended them and whether there are any notes, transcripts or documents about them, two of the people said. Among the matters Mr. Mueller wants to ask the officials about is President Trump’s decision in May to fire the F.B.I. director, James B. Comey, the two people said. 

Mueller is particularly interested in one former Trump adviser in particular, and that name in particular may sound alarm bells:

Mr. Mueller has expressed interest in speaking with other administration officials, including members of the communications team. But Mr. Trump’s allies are particularly concerned about Mr. Mueller’s interest in talking to Mr. Priebus, a former chairman of the Republican National Committee who worked closely with Mr. Trump during the presidential campaign. Mr. Trump’s confidants at the White House say Mr. Trump was never fully convinced that Mr. Priebus would be loyal to him. [...]

Mr. Priebus can potentially answer many questions Mr. Mueller has about what occurred during the campaign and in the White House. Mr. Priebus appears on the calendar of Mr. Manafort on the same day in June 2016 that Mr. Manafort and other campaign officials — including Mr. Trump’s eldest son and son-in-law — attended a meeting with Russians who claimed to have damaging information about Hillary Clinton, according to two people briefed on the matter. It is not clear whether Mr. Priebus and Mr. Manafort met that day.

Priebus was basically Trump’s babysitter, so he’s in a position to know uncomfortable details about Trump’s thoughts, words, and actions at the time.

Again, we knew Mueller would get around to interviewing people in the White House. But that doesn’t mean Trump (or his lawyers) will be happy that it’s already happening.