Stephen K. Bannon, who was ousted as White House chief strategist last summer but has remained in touch with some members of President Trump’s circle, is pitching a plan to West Wing aides and congressional allies to cripple the federal probe into Russian interference in the 2016 election, according to four people familiar with the discussions.

The first step, these people say, would be for Trump to fire Deputy Attorney General Rod J. Rosenstein, who oversees the work of special counsel Robert S. Mueller III and in recent days signed off on a search warrant of Trump’s longtime personal lawyer, Michael Cohen.

Bannon is also recommending the White House cease its cooperation with Mueller, reversing the policy of Trump’s legal team to provide information to the special counsel’s team and to allow staff members to sit for interviews.

And he is telling associates inside and outside the administration that the president should create a new legal battleground to protect himself from the investigation by asserting executive privilege — and arguing that Mueller’s interviews with White House officials over the past year should now be null and void.