In an interview with Fox News on Wednesday night, Giuliani told host Laura Ingraham "I don't know," when asked if there was a spy in the 2016 campaign.
Giuliani, however, resurfaced the concept later on when discussing what he said were instances of misconduct.
"What they did with Manafort, what they did with Michael Cohen, all the illegitimate things they’ve done — possibly placing a spy in the Trump campaign,” Giuliani said. He was referring to last month's FBI raids on Trump's personal attorney, Michael Cohen's, home and office, and of former Trump campaign head Paul Manafort's home.
“All these things are areas where indictments have been dismissed because of government misconduct,” Giuliani said.
“I do not understand what Bob was thinking of, hiring these people,” he added, referring to special counsel Robert Mueller.
Trump has repeatedly slammed Mueller's probe into alleged ties between his presidential campaign and Russian meddling in the 2016 election as a “witch hunt” and has called for the special counsel's investigation to end on numerous occasions.
Giuliani also called for the end of Mueller's probe during the interview Wednesday.
More about: FBI