NBC News, which did not identify the Russian-American lobbyist, said some U.S. officials suspected him of having ongoing ties to Russian intelligence, something he denied to the network.
The Associated Press said the lobbyist, whom it identified as Rinat Akhmetshin, confirmed that he had attended the June 2016 meeting in New York's Trump Tower. Despite intense media focus on the meeting, his presence had not been reported or disclosed until Friday.
Emails disclosed by Donald Trump Jr. this week showed him eager to attend the meeting with the lawyer, Natalia Veselnitskaya, after learning that she might have information damaging to Democratic presidential candidate Hillary Clinton.
Last weekend's revelation of the Trump Tower gathering would be the most tangible evidence of a connection between Trump's 2016 campaign and Russia, a subject that has also prompted investigations by congressional committees and federal special counsel.
Trump's son-in-law, Jared Kushner, and former campaign adviser Paul Manafort were also at the meeting.
Accusations that Moscow meddled in the election and colluded with the Trump campaign have dominated the Republican president's first months in office. Russia denies the allegations, and Trump says there was no collusion.
U.S intelligence agencies said earlier this year that Russia sought to help Trump win the election by hacking private emails from Democratic Party officials and disseminating false information online.
A Soviet Past
NBC News said the Russian-born American lobbyist who attended the meeting with Trump aides had served in the Soviet military and emigrated to the United States, where he holds dual citizenship. He denied any current ties to Russian spy agencies.
The White House had no immediate comment about the NBC News report.
NBC News said representatives for Kushner and Manafort declined to comment, but that a lawyer for Trump Jr. said he had spoken to the lobbyist.
Democratic Senator Dick Durbin said Trump Jr. was wrong not to mention the presence of the Russian-American lobbyist when he acknowledged this week that the meeting took place.
"Basic rules in Washington: It's not the crime, it's the cover-up, and secondly when you make a disclosure, make it complete," Durbin told MSNBC. "What we have here is a slow bleed, more and more information coming out, discrediting some of the representations that have been made by Donald Trump Jr. and others about this meeting."
Trump Jr.'s lawyer, Alan Futerfas, said he had talked with the person who came to the meeting with Veselnitskaya.
"He is a U.S. citizen,” Futerfas told NBC News. "He told me specifically he was not working for the Russian government, and in fact laughed when I asked him that question."
The lawyer said Trump Jr. knew nothing about the man's
background at the time of the meeting.
Trump told Reuters on Wednesday that he did not know about his son's meeting until recently. But in a conversation with reporters later that day, Trump said: "In fact, maybe (the meeting) was mentioned at some point," adding he was not told it was about Clinton.
The president's legal team was informed more than three weeks ago about the email chain arranging the meeting between Trump Jr. and the Russian lawyer, two sources familiar with the handling of the matter told Yahoo News.
Banner/thumbnail credit: Reuters