The somewhat vague tweet seems to refer to Rosenstein, who wrote a memo outlining an argument against then-FBI director James B. Comey. The White House initially claimed that Rosenstein's memo contributed to Trump's decision to fire Comey. But later, Trump said in an interview that he would have fired Comey “regardless” of Rosenstein's recommendation.
Adding to the confusion is the fact that the special investigation is currently being led by another former FBI director. Robert Mueller reports to Rosenstein, but is authorized to pursue the investigation independently. And there is no evidence that Mueller recommended to Trump that he fire Comey.
Trump also seemed to confirm reports in The Washington Post and other publications that Mueller's investigation has expanded to include allegations that he attempted to obstruct the ongoing investigation into Russian meddling in the election and his campaign associates' possible collusion with Russians.
A White House spokeswoman declined to comment and referred questions to Trump's personal attorney Marc Kasowitz. A spokesman for Kasowitz said that the president was referring to the Washington Post report "based on anonymous, illegal leaks."
On Thursday night, Rosenstein issued a statement casting doubt on news stories based on anonymous sources, notably from unidentified countries. News reports (including in The Washington Post) have detailed parts of the special counsel's investigation.
"Americans should exercise caution before accepting as true any stories attributed to anonymous ‘officials,’ particularly when they do not identify the country — let alone the branch of agency of government — with which the alleged sources supposedly are affiliated," Rosenstein's statement said. "Americans should be skeptical about anonymous allegations."
"The Department of Justice has a long established policy to neither confirm nor deny such allegations," he continued.
Trump sent more tweets early Friday morning attacking the investigation as “phony.”
“After 7 months of investigations & committee hearings about my “collusion with the Russians,” nobody has been able to show any proof. Sad!” Trump tweeted. “Despite the phony Witch Hunt going on in America, the economic & jobs numbers are great. Regulations way down, jobs and enthusiasm way up!”
Trump's comments came as lawyers for his presidential transition ordered former staffers to preserve all physical and electronic documents in order to comply with ongoing Russia investigations.
The memo identifies several Trump officials and advisers whose records are of particular interest in the probe. They are former Trump campaign manager Paul Manafort, his business partner Rick Gates, a national security adviser Carter Page, retired Lt. Gen. Michael Flynn, and informal Trump adviser Roger Stone.
“Failure to follow these protocols could result in criminal or civil penalties, and could form the basis of legal claims, legal presumptions, or jury instructions relating to spoliation of evidence,” the memo states.