Barr works closely with CIA Director Gina Haspel, National Intelligence Director Dan Coats and FBI Director Christopher Wray.
Trump often called on the Ministry of Justice and others to review how the FBI investigated the link between its election campaign and Russia's interference in the 2016 elections. He told reporters on Tuesday that he did not tell Barr to ask the intelligence services to join his review of the Russian investigation.
"I did not ask him," Trump told the White House before leaving for Louisiana. "I did not know."
"But I think it's great that he did it, I saw it last night, and they want to see how all this dizziness started," he continued. I'm so proud of our attorney general that he thinks about it, I think it's great. "
"I think it's a big deal to spy on a political campaign," Barr then told Congress.
The DNI and the CIA did not immediately respond to a request for comment.
Trump and his GOP allies on Capitol Hill repeatedly claimed – without evidence – that a 2016 arrest warrant, which allowed the FBI to monitor Page, was evidence of abuse of supervision by the Department of Justice and the FBI ,
Conservative critics of Special Envoy Robert Mueller have argued that his work came from the fruit of a poisonous tree, suggesting that the application for the FISA arrest warrant was fouled as he created some of those retired by British spy Christopher Steele Contained documents for which he was paid by Democrats. They also point out that the FBI is using an informant to meet former Trump campaign adviser George Papadopoulos.
Democrats claim, however, that Page's FISA arrest warrant was justified on the basis of its contacts with Russia, and that the FBI and the Ministry of Justice were acting properly to approve the warrant and its subsequent extension by the Foreign Intelligence Surveillance Court.
This story has been updated.
Veronica Stracqualursi of CNN contributed to this report.