Mr. Trump said he felt “somewhat” vindicated by the revelations.

Communications of Donald Trump’s transition officials, possibly including the incoming President himself, may have been scooped up in legal surveillance but then improperly distributed throughout the intelligence community, the chairman of the House intelligence committee said Wednesday.

In an extraordinary set of statements to reporters, Republican Rep. Devin Nunes said the intercepted communications do not appear to be related to the ongoing FBI investigation into Mr. Trump associates’ contacts with Russia or any criminal warrants.

Mr. Nunes, who served on Mr. Trump’s transition team, said he believes the intelligence collections were done legally but that identities of Mr. Trump officials and the content of their communications may have been inappropriately disseminated in intelligence reports.

“What I’ve read bothers me, and I think it should bother the President himself and his team,” Mr. Nunes said Wednesday after briefing Mr. Trump privately at the White House.

Mr. Trump said he felt “somewhat” vindicated by the revelations, despite the fact that Mr. Nunes said the new information did not change his assessment that the president’s explosive claim that Barack Obama wiretapped his New York skyscraper was false.

Shortly after being briefed by the California congressman, Mr. Trump told reporters, “I very much appreciated the fact that they found what they found.”

It was unclear whether Mr. Trump’s own communications were monitored. Mr. Nunes initially said “yes” when asked if Mr. Trump was among those swept up in the intelligence monitoring, but then said it was only “possible” that the President’s communications were picked up.

Mr. Nunes said the information on the Mr. Trump team was collected in November, December and January, the period after the election when Trump was holding calls with foreign leaders, interviewing potential Cabinet secretaries and beginning to sketch out administration policy. Mr. Nunes said the monitored material was “widely disseminated” in intelligence reports.

Asked whether he believed the transition team had been spied on, Mr. Nunes said, “It all depends on one’s definition of spying.”