Special counsel Robert Mueller is reportedly seeking to interview White House staffers who were present at the time President Trump dictated Donald Trump Jr.’s initial statement on a controversial meeting he had with a Russian lawyer ahead of the 2016 presidential election, CNN reported Thursday.

According to the report, Mueller and his investigative team want to speak with those involved in order to see if relevant details were purposefully left out and probe how the misleading statement came to be. 

These staffers, who may include top aides to the president, have not yet been interviewed, one source told CNN.

Mueller has not yet requested to interview the president, but only a handful of people he believes could be possible witnesses to the event.

{mosads}The president’s eldest son has become a key figure in the various Russia probes after meeting with a woman — described as a Russian government lawyer — who was offering dirt on then-Democratic presidential nominee Hillary Clinton.

Trump Jr. has denied that he received any damaging information about Clinton after taking the meeting. 

Trump Jr.’s first response on the matter claimed that he “primarily discussed a program about the adoption of Russian children,” which was later shown to be false after he released his email correspondence about setting up the meeting. It was later reported that the president helped dictate the first statement by Trump Jr.

News of Mueller’s interest in Trump aides and the statement on Trump Jr.’s meeting signals that the special counsel is interested in learning more about the intent and decision-making behind the statement and the meeting itself.

The report comes hours after Trump Jr. met with Senate investigators behind closed doors.

“Out of respect for the special counsel process, the White House doesn’t comment on any individual special counsel request,” White House special counsel Ty Cobb told the news outlet.

Mueller’s office declined CNN’s request for comment on the story.