A lawyer who has been in contact with Mr Mueller’s team was quoted as saying: “They clearly are tying up loose ends.” Robert Mueller has been investigating potential Russian collusion with the Trump presidential campaign since the president took office. But the sources NBC cited said Mr Mueller still has not answered the fundamental question he was hired to answer.
The American attorney has not yet made public any evidence proving the alleged conspiracy.
However, he has refuted claims by the President neither he or his top team met with or had talks with Russians during the 2016 race.
Mr Mueller’s spokesman, Peter Carr, declined to comment to NBC.
The President’s lawyer, Jay Sekulow, said, “We don’t discuss conversations we’ve had or have not had with the office of special counsel.”
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Mr Mueller was appointed in May 2017 following Trump’s decision to fire former FBI director, James Comey.
The dismissal of the security chief was embroiled in controversy and led to heightened speculation of Trump-Russia collusion.
Mr Comey was critical of the Trump administration for its handling of the Hilary Clinton email controversy and potential Russian collusion.
A letter Trump drafted to the former FBI director is now in Mr Mueller’s possession.
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Mr Mueller has also been tasked with examining whether Trump obstructed the course of justice.
He is expected to address the matter is his report.
But whether or not the senior lawyer will accuse Trump of that wrongdoing is not clear.
A total of 33 people have already been charged and convicted in connection with the case.
They include Trump’s former campaign manager Paul Manafort, former National Security Adviser Mike Flynn and lawyer Michael Cohen — who have cooperated with him to varying degrees.