A spokesperson for former President Barack Obama on Saturday flatly rejected President Donald Trump’s claim that the Obama administration illegally wire tapped his campaign headquarters during the 2016 race.

Trump’s allegation, made in a string of tweets that offered no evidence of the information’s source, was “simply false,” Obama spokesman Kevin Lewis said in a statement.

“Neither President Obama nor any White House official ever ordered surveillance on any U.S. citizen,” Lewis said.

Neither @barackobama nor any WH official under Obama has ever ordered surveillance on any US Citizen. Any suggestion is unequivocally false pic.twitter.com/qF04X3NUvq — Kevin Lewis (@KLewis44) March 4, 2017

Trump charged that Obama had his “wires tapped” in Trump Tower a month ahead of the election, comparing the alleged surveillance to “McCarthyism” and the Watergate scandal.

The President did not mention where he learned this information, which he said he “just found out.” Breitbart News this week published a piece based on claims made by conservative radio host Mark Levin alleging that Obama carried out a “silent coup” against the Trump campaign using “police state” tactics.

The Guardian and Heat Street have reported that the FBI applied for a foreign intelligence surveillance court (FISA) warrant over the summer to monitor four Trump staffers suspected of having improper ties to Russian officials. The initial request was turned down for being overly broad, but according to Heat Street, the FBI eventually received a warrant in October after the discovery of a server in Trump Tower connected to a Russian bank.