Here's how we'll know for sure if Paul Manafort visited Julian Assange in London embassy

On Tuesday morning, the Guardian newspaper reported that Trump campaign boss Paul Manafort secretly met with Julian Assange of Wikileaks at the Ecuadorian embassy in London.

The news came the day after it was revealed that special counsel Robert Mueller was seeking to call off his cooperation agreement with Manafort because the Trump campaign boss allegedly lied while offering evidence.

CNN's Brooke Baldwin discussed the developments with CNN's chief political columnist Dana Bash and Garrett Graff, who wrote a book about the FBI under Mueller. Baldwin wanted to know whether the developments with Manafort meant prosecutors could prove something like the allegations revealed by the Guardian. Wikileaks is denying that the meeting happened.

"I don't think that Paul Manafort was going in there to get restaurant recommendations for a great night out in London," Graff said.

Graff also pointed out that Ecuador has removed the ambassador that was Assange's ally in London and have blocked Assange from meeting with his lawyers.

"There is some speculation that maybe they are preparing to turn Julian Assange over to U.S. authorities," he said.

"Wouldn't it be easy to prove Manafort was there?" Baldwin asked. "Flight records, security surveillance cameras, etc.?"

"London is the most watched city in the western world and if Manafort was there, there is almost certainly CCTV camera footage of that happening and of course Paul Manafort's travel records of him coming in and out of London as well," he said.

Watch the segment below.