U.S. President Donald Trump on Friday denied he was "agitated" about the Russian Federation investigation and said he has answered written questions from special counsel Robert Mueller but hasn't yet submitted them.
Since then the two sides have reportedly jousted over whether the president had to answer and how he would do so - including the possibility that he would submit to a face-to-face interview with prosecutors.
Mueller, who Rosenstein named to head the Russian Federation investigation in May 2017, is investigating whether members of Trump's campaign conspired with Moscow in the 2016 election and whether Trump has unlawfully sought to obstruct the probe, which has cast a cloud over his presidency. "I wrote the answers", he said.
WATCH: As President Trump's war against Robert Mueller escalates, so too does the Congressional push for legislation protecting the special counsel from being fired.
"The questions were very routinely answered by me, " said Donald Trump.
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Mr Trump's team agreed to have the President submit written answers to questions relating to Russia's role in the election, but it is still possible Mr Mueller may press Mr Trump to answer questions on potential obstruction at some point. Another person familiar with the effort said they expect Trump to turn over the answers before Thanksgiving.
"The inner workings of the Mueller investigation are a total mess, " Trump tweeted on Thursday as part of a series of overheated morning posts.
He also called the investigation a "witch hunt" and a "hoax", terms he has also used to describe it in the past. "I'm sure they're tricked up, because you know they like to catch people - "Gee was the weather sunny or was it raining...he said it may have been a good day, it was raining therefore he told a lie, her perjured himself" - okay, so you have to always be careful when you answer questions with people who probably have bad intentions".
A team of investigators led by Mr Mueller is looking into whether anyone from Mr Trump's campaign colluded in the effort. "I imagine it's ending now", Trump added. "I write answers", he said. "They have found no collusion and have gone absolutely nuts".
Four people connected with Mr Trump's campaign and presidency - campaign chairman Paul Manafort, advisers Rick Gates and George Papadopoulos, as well as former national security adviser Michael Flynn - have been charged and further indictments could be issued.