Asked about Trump’s tweets on Saturday, a former senior US official with direct knowledge of investigations by the Justice Department under the Obama administration denied there was any such investigation of Trump or that his phones were tapped.

“This did not happen. It is false. Wrong,” the former official said.

The official said clearly that Obama could not order this. It would have been taken to a judge by investigators, but investigators never did that, the former official said.

Trump did not offer evidence for his stunning claim, which has not been verified, and the White House did not immediately return requests for comment Saturday morning. An Obama spokesman had no comment regarding Trump’s claims.