Washington (CNN) The special counsel investigating potential ties between Donald Trump's presidential campaign and Russia has obtained a draft of a letter that explains reasons why Trump planned to fire former FBI Director James Comey, The New York Times reported Friday.

The Justice Department turned over a copy of the letter, which was drafted by Trump and top aide Stephen Miller, to Mueller in recent weeks, the Times reported, citing interviews with a dozen administration officials and others briefed on the matter.

The Times report doesn't say what was in the letter, which was originally meant to be sent directly to Comey, according to the Times. Ty Cobb, a White House lawyers, declined to discuss the letter or its contents to the Times.

But it was met with opposition from White House counsel Don McGahn, who saw its contents as "problematic," the Times reported.

Instead, a letter written by Deputy Attorney General Rod Rosenstein that was focused on criticizing Comey's handling of the investigation into Hillary Clinton's private email server was cited behind Trump's decision to fire the FBI chief.

Read More