Trump lawyer Ty Cobb is leaving the president's team dealing with special counsel Robert Mueller's investigation and will be replaced by Emmet Flood, who represented President Bill Clinton during his impeachment.

Cobb's departure and Flood's arrival is just the latest shuffling of President Donald Trump's legal team to deal with Mueller's investigation into Russian interference in the 2016 presidential election. And it reportedly is due to a desire to be more aggressive in responding to that probe.

"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 this month," White House spokeswoman Sarah Huckabee Sanders said in a prepared statement Wednesday.

"Emmet Flood will be joining the White House Staff to represent the President and the administration against the Russia witch hunt," Sanders said.

"Ty Cobb, a friend of the President, who has done a terrific job, will be retiring at the end of the month."

The moves were first reported by The New York Times.

Flood, a Washington lawyer, was said to be in discussions with Trump two months ago about joining his legal team for Mueller's probe.

The Times reported that Flood is expected "to take a more adversarial approach" to Mueller's investigation that Cobb, 68, who has advocated for cooperation with Mueller's probe. When he was hired last summer, Cobb said that the White House was "in full cooperation mode."

But the White House now may be less cooperative.