'The president's insane': Senior Trump official confides in insider account of White House
President Donald Trump. (Isac Nóbrega/PR)

In a review of CNN's  Jim Acosta's forthcoming book,  "The Enemy of The People," Guardian reviewer Martin Pengelly reveals some telling quotes that the CNN White House correspondent relays, including one White House official confiding that President Donald Trump is mentally ill.

According to the report,  Acosta's sources "are often blunt in their assessment of their boss. A 'senior White House official' tells Acosta: 'The president’s insane.' A 'former White House national security official says staffers were not sure the president had not been 'compromised' by Russia."

As Pengelly explains, "The notion that the media was the 'enemy of the people' emerged swiftly and caused great consternation among a press corps spooked by virulent abuse at Trump rallies. Acosta cites three unnamed sources who say the controversial line of attack originated with Steve Bannon, then Trump’s chief White House adviser."

"In his book, Acosta admits to sometimes 'grandstanding' and 'showboating,'" the reviewer explains. "He also says he 'opts for the bait' when questioning Trump, 'which bothers some people.' Of concerns he may be biased against the president, he writes: 'Neutrality for the sake of neutrality doesn’t really serve us in the age of Trump'."

Acosta's book also notes that combative White House spokesperson Sarah Sanders has been known to socialize and have drinks with the very reporters she disparages in her constant attacks on the press.