Without attacking author Michael Wolff's account - or even directly apologizing for the substance of his own remarks - Bannon affirmed his allegiance to Trump.
President Trump was the only candidate that could have taken on and defeated the Clinton apparatus.
Unity Books in Wellington said they had had lots of pre-orders and requests for the book and they're expecting a big delivery.
Wolff's book, "Fire and Fury - Inside the Trump White House", portrays Trump as unfocused, unprepared and petty while presiding over a chaotic White House.
"As I said during my interview with "60 Minutes" and many times since, there is no basis to the Russian investigation".
Reagan, the Republican US president from 1981-1989, was diagnosed with Alzheimer's disease in 1994 and died in 2004.
In his statement Sunday, Bannon said his comments were not intended as a slight against the president's son.
Arsenal vs Chelsea: Controversy as Bellerin rescues point for Gunners
I try to serve this game with honesty and integrity and when I have something to say, I say it'. It's not been possible to write off Arsenal's prospects so early under the manager.
White House Chief of Staff John Kelly told reporters at Camp David that he had not been aware of Trump's morning tweets.
And when Trump addressed reporters later, the Ivy League graduate was ready for the question.
Wolff's book, published Friday, paints Trump as a leader who doesn't understand the weight of his office and spends his evenings eating cheeseburgers in bed, watching television, and talking on the phone to old friends.
CIA Director Mike Pompeo, who said Trump was "completely fit" to lead the country, said he paused before answering because it was such "a ludicrous question".
Chatter about Trump's mental fitness for office has intensified in recent months on cable news shows and among Democrats in Congress.
White House spokeswoman Sarah Huckabee Sanders this week called such suggestions "disgraceful and laughable".
But he said that Trump didn't appear angry Friday or Saturday. "Trump is going to get worse and will become uncontainable with the pressures of the presidency".
In early December, members of the Senate and House met with Yale psychiatrist Dr.
Nikki Haley, the USA ambassador to the United Nations, said that she is at the White House once a week, and "no one questions the stability of the president".