After months of negotiations, this move represents an important development and signals that the Mueller investigation could enter a final phase with respect to the President.
The questions focus on issues surrounding investigating possible collusion between Trump employees and Russians seeking to interfere in the 2016 elections. Trump's lawyers prepared written replies, relying in part on documents previously provided to the Special Adviser.
"We are in constant dialogue with the Special Adviser and do not comment on these discussions," said Trump lawyer Jay Sekulow
After the first answer, there may be more questions. The Special Adviser had insisted that follow-up questions were also possible. But after a long back and forth over months, both sides agreed to start with a first round of questions.
In addition, the two sides have still not agreed on whether the president will be personally interviewed by investigators who are also investigating whether Trump has obstructed the judiciary by dismissing FBI director James Comey.
Asked on Thursday if he wanted to answer Mueller's questions, Trump again signaled his willingness to sit down for an interview with Müller or give written answers ̵
"It seems ridiculous for me to do it if everyone says there is no collusion, but I'll do what's necessary to get it over with, "Trump said in a telephone interview on Fox News. Despite Trump's insistence on the contrary, the possibility of collusion remains an open question in the ongoing investigation led by Mueller, who has not tipped his hand in one direction or the other.
CNN's Marshall Cohen contributed to this story.