President Trump will shut down the government if Congress doesn’t provide funding for the wall this year, former top aide Stephen K. Bannon reveals in a new biography.

In Bannon: Always the Rebel, from White House reporter and former Examiner editor Keith Koffler, Trump is described as constantly telling aides he will build the wall, a key campaign promise.

“He has re-emphasized to me 100 times: We must build the wall,” Bannon told Koffler in the book from Regnery Publishing and being released Monday.

“The wall is going to take on totemic value. He is bound and determined. And by the way, if that takes shutting down the government, you know, he may have to do it,” added Bannon.

Bannon, who left the White House in summer to return to Breitbart News, said in the biography that Trump has already logged successes in his immigration policies, and wants more.

But the wall stands as the symbol of his policies. Funding requests are before Congress and several prototypes have been unveiled on the U.S.-Mexico border.

Democrats have pledged to fight funding in budget legislation moving through Congress.

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at