The known participants include Trump Jr., his brother-in-law Jared Kushner, Goldstone, and then-campaign chairman Paul Manafort.
Trump Jr.'s attorney, Alan Futerfas, told Fox News he could not confirm Samochornov was at the meeting, but said one of the two other attendees was a US citizen.
Emails posted by Trump Jr. show that he was told by an associate that the meeting was part of a Russian government effort to help Donald Trump in the election. Veselnitskaya told NBC News she had at least one other guest with her in the meeting, but declined to say who he was.
But Ms Veselnitskaya was described by a United States businessman who will give testimony to a Senate committee against her as a "well-resourced player".
President Trump has defended his son's conduct, saying Thursday that "most people would have taken that meeting". "Two other people in the room, I guess one of them left nearly immediately and the other one was not really focused on the meeting".
But Trump Jr. quickly lost interest when, as he pressed her to back up her allegations, Veselnitskaya admitted the Trump campaign would have to do its own research to prove the information.
Russian-born American lobbyist served in the Soviet military and emigrated to the US, where he holds dual citizenship.
Agalarov is a well-known musician and client of Rob Goldstone, who arranged the meeting between Trump Jr. and Veselnitskaya.
President Trump continues to insist he didn't know anything about the meeting until several days before Donald Trump Jr.'s emails were released.
To help the White House deal with Russia-related investigations, Trump is hiring veteran Washington lawyer Ty Cobb, a source familiar with the matter said on Friday.
Kushner is set to cooperate in the upcoming weeks with both the House and Senate intelligence committee probes into alleged Russian interference in the 2016 election.
Asked about Akhmetshin and his possible participation in the June 2016 meeting, Dmitry Peskov, spokesman for Russian President Vladimir Putin, told reporters on Friday: "We don't know anything about this person". He emigrated to the U.S. He got dual citizenship about eight years ago.
"He said, 'I think he accepted it, but you'll have to ask him.' That's a big difference". -Russian adoption program. On Sunday, Trump Jr. confirmed he had been promised information "helpful to the campaign" and he had asked Manafort and Kushner to "stop by". And here's the important point - this meeting likely was not the last on this topic, likely not the only one.
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It also was suggested that if the president attended the event it would take the spotlight from the players. She didn't get much in the way of sleep as she travelled here overnight, arriving during the day Monday.
Wimbledon: Federer Beats Berdych, Faces Cilic In Final
I have a lot of respect for him doing that. "Really, I can not be in a better position before Friday's match", Berdych said. Federer leads Cilic 6-1 in career meetings. "Being favourite or not the favourite doesn't matter", said Federer .
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Shortly after arriving in France on Friday, President Donald Trump commented on the physical appearance of France's first lady. He had also added that the United States was walking out of the accord as it was putting USA industry at risk.
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He said at a press conference: "I genuinely haven't been on my phone for the last couple of days, I've tried to switch off". The success of London Live is likely to encourage Liberty to continue pushing for similar events in other cities.
Querrey tops Murray; Djokovic out; Federer wins
His victories have been even more astounding considering that Federer hadn't won a Grand Slam tournament since 2012. Coverage across BBC TV, BBC Radio and BBC Sport website with further coverage on Red Button, Connected TVs and app.