Mr. Trump, who has mounted a yearslong attack on the intelligence agencies, is particularly difficult to brief on critical national security matters, according to interviews with 10 current and former intelligence officials familiar with his intelligence briefings.

The president veers off on tangents and getting him back on topic is difficult, they said. He has a short attention span and rarely, if ever, reads intelligence reports, relying instead on conservative media and his friends for information. He is unashamed to interrupt intelligence officers and riff based on tips or gossip he hears from the former casino magnate Steve Wynn, the retired golfer Gary Player or Christopher Ruddy, the conservative media executive.

Mr. Trump rarely absorbs information that he disagrees with or that runs counter to his worldview, the officials said. Briefing him has been so great a challenge compared with his predecessors that the intelligence agencies have hired outside consultants to study how better to present information to him.