The lawyer leading US president Donald Trump’s response to the special counsel investigation into Russian interference in the 2016 election is to resign.
News of Ty Cobb's departure from his post came as tensions between the Trump administration and special counsel Robert Mueller deepened.
Amid reports that Mr Mueller may subpoena the president to appear before him, the White House confirmed that Mr Trump's long-time lawyer would depart at the end of the month.
"For several weeks Ty Cobb has been discussing his retirement and last week he let chief of staff [John] Kelly know he would retire at the end of the month," White House press secretary Sarah Huckabee Sanders said in a statement.
Mr Cobb is being replaced by Emmet Flood, a veteran attorney who was part of the legal team that represented Bill Clinton during his impeachment trial. He would represented the Trump administration against "the Russia witch hunt", Ms Huckabee Sanders said.
In a separate development, Rudy Giuliani, the former New York mayor who joined Mr Trump's legal team last month, responded to reports of a possible 12-hour interview of the president by the special counsel. "If it [the interview] happens, that's not going to happen, I'll tell you that. It would be, max, two to three hours around a narrow set of questions," he told the Washington Post.
His comments came on the back of a Washington Post report that Mr Mueller's team warned Mr Trump's team in March that he could issue a subpoena for the president to appear before a grand jury if Mr Trump did not comply with an interview request.
Russia investigation
Earlier this week, the New York Times published 49 questions they said Mr Mueller's team is preparing to ask the US president as part of the Russia investigation.
Mr Cobb’s departure is the latest shake-up in the president’s legal team as negotiations continue between the White House and Mr Mueller about a possible interview.
Mr Trump's personal lawyer, Michael Cohen, was subject to a raid by FBI officers last month, and is seeking to limit the access investigators can have to his legal documents.
Mr Giuliani played down the significance of Mr Cobb’s departure. “It was just time for him to go, but he’s still going to be available to us,” he said. Mr Cobb is reported to have been the Trump team’s main contact point for the Mueller investigation.
Earlier in the day, Mr Trump had lashed out at the investigation. "There was no Collusion (it is a Hoax) and there is no Obstruction of Justice (that is a setup & trap)," he said, adding: "What there is is Negotiations going on with North Korea over Nuclear War, Negotiations going on with China over Trade Deficits, Negotiations on NAFTA, and much more. Witch Hunt!"
Mr Trump also waded into the controversy surrounding deputy attorney general Rod Rosenstein, who has been locked in dispute with senior Republicans in Congress, some of whom have drafted impeachment proceedings against him over his role in sanctioning FBI surveillance of former Trump aide Carter Page.
Unredacted memo
The department of justice has told Republican members it will not provide the committee with an unredacted version of a memo outlining the scope of the Mueller investigation. Mr Rosenstein, the second-highest official at the department, is in charge of the special counsel investigation after attorney-general Jeff Sessions recused himself.
In a tweet, Mr Trump threatened to intervene in the issue. “Rigged System – They don’t want to turn over Documents to Congress. What are they afraid of? Why so much redacting? Why such unequal ‘justice?’ At some point I will have no choice but to use the powers granted to the Presidency and get involved!”
The president’s comments came a day after Mr Rosenstein said the justice department was “not going to be extorted” by public and private threats.
Senate minority leader Chuck Schumer warned the president against getting involved in the controversy. "Mr President, the powers of the Presidency do not give you the right to interfere with or shut down the Russia investigation. Firing the deputy AG or director Mueller would create a constitutional crisis. Do not go down this road."