"Since the December meeting, they have discussed whether the president could provide written answers to some portion of the questions from Mueller’s investigators, as then-President Ronald Reagan did during the Iran-contra investigation," according to the newspaper. "They have also discussed the obligation of Mueller’s team to demonstrate they could not obtain the information they are seeking without interviewing the President."
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Mueller’s investigation, launched in May 2017, has led to charges against several people connected to the Trump presidential campaign and its officials. The president’s former campaign chairman Paul Manafort has pleaded not guilty to a variety of money laundering and other criminal charges stemming from the probe. Five people -- including former White House national security adviser Michael Flynn and former Trump campaign aides Rick Gates and George Papadopoulos -- have pleaded guilty and agreed to cooperate with investigators.
>> Related: Mueller could interview Trump in Russia probe: report
Thirteen Russians and three Russian organizations have also been indicted on charges of interfering in the election.
A judge on Tuesday handed down a 30-day jail sentence for Dutch attorney Alex van der Zwaan, who admitted in February to lying to investigators about his conversations with Gates and with an unidentified person linked to Russian intelligence, according to The Los Angeles Times.