Washington (CNN) Special counsel Robert Mueller has been reviewing President Donald Trump's Twitter feed as part of the former FBI director's probe into obstruction of justice, The New York Times reported Thursday.

The Times, citing three people briefed on the matter, said Mueller was also combing through negative statements from Trump toward Attorney General Jeff Sessions and former FBI Director James Comey. The report said Mueller wanted to question Trump about the tweets and that the public statements from Trump on his preferred social media platform add to an obstruction investigation, which includes Trump's private statements to Comey and others about the Russia investigation as well as potential pardon offers to people who could end up as witnesses.

Trump's lawyers told the Times that none of what was under review amounted to obstruction of justice, although the report said privately some of those lawyers had expressed concern about what Mueller would be able to argue when taking many efforts and messages together.

News of the review of Trump's public statements that might touch on obstruction of justice came as Trump's lawyers and the special counsel team have continued not to reach an agreement on a sitdown interview between the President and Mueller. A list of topics earlier this year showed Mueller was interested in for a potential interview included a focus on Sessions and Comey, with explicit references to tweets Trump had sent about Comey and his criticism of Sessions last July, when Trump aired grievances about Sessions on Twitter.

Trump has said he would be willing to sit for an interview, and Trump's lawyers have sought to narrow the scope of such an interview, with Trump's attorney Rudy Giuliani offering varying statements about an interview since joining the team.