WASHINGTON (NYTIMES) - Two weeks after Donald Trump clinched the Republican presidential nomination last year, his eldest son arranged a meeting at Trump Tower in Manhattan with a Russian lawyer who has connections to the Kremlin, according to confidential government records described to The New York Times.

The previously unreported meeting was also attended by Trump's campaign chairman at the time, Paul Manafort, as well as the president's son-in-law, Jared Kushner, according to interviews and the documents, which were outlined by people familiar with them.

While Trump has been dogged by revelations of undisclosed meetings between his associates and Russians, this episode at Trump Tower on June 9, 2016, is the first confirmed private meeting between a Russian national and members of Trump's inner circle during the campaign.

It is also the first time that his son Donald Trump Jr is known to have been involved in such a meeting.

Representatives of Trump Jr and Kushner confirmed the meeting after The Times approached them with information about it.

In a statement, Trump Jr described the meeting as primarily about an adoption programme. The statement did not address whether the presidential campaign was discussed.

US intelligence agencies have concluded that Russian hackers and propagandists worked to tip the election towards Donald Trump, and a special prosecutor and congressional committees are investigating whether his campaign associates colluded with Russians. Trump has disputed that, but the investigation has cast a shadow over his administration for months.

Trump has also equivocated on whether the Russians were solely responsible for the hacking. But in Germany on Friday (July 7), meeting President Vladimir Putin for the first time as president, Trump questioned him about the hacking. The Russian leader denied meddling in the election.

The Russian lawyer invited to the Trump Tower meeting, Natalia Veselnitskaya, is best known for mounting a multipronged attack against the Magnitsky Act, a US law that blacklists suspected Russian human rights abusers. The law so enraged Putin that he retaliated by halting American adoptions of Russian children.

The adoption impasse is a frequently used talking point for opponents of the Magnitsky Act. Veselnitskaya's campaign against the law has also included attempts to discredit its namesake, Sergei L. Magnitsky, a lawyer and auditor who died in mysterious circumstances in a Russian prison in 2009 after exposing one of the biggest corruption scandals during Putin's rule.

Veselnitskaya was formerly married to a former deputy transportation minister of the Moscow region, and her clients include state-owned businesses and a senior government official's son, whose company was under investigation in the United States at the time of the meeting. Her activities and associations had previously drawn the attention of the FBI, according to a former senior law enforcement official.

In his statement, Trump Jr said: "It was a short introductory meeting. I asked Jared and Paul to stop by. We primarily discussed a program about the adoption of Russian children that was active and popular with American families years ago and was since ended by the Russian government, but it was not a campaign issue at the time and there was no follow up."

He added: "I was asked to attend the meeting by an acquaintance, but was not told the name of the person I would be meeting with beforehand."

Late Saturday, Mark Corallo, a spokesman for the president's lawyer, issued a statement implying that the meeting was a set-up. Veselnitskaya and the translator who accompanied her to the meeting "misrepresented who they were", it said.

In an interview, Corallo explained that Veselnitskaya, in her anti-Magnitsky campaign, employs a private investigator whose firm, Fusion GPS, produced an intelligence dossier that contained unproven allegations against the president.

Trump Jr had denied participating in any campaign-related meetings with Russian nationals when he was interviewed by The Times in March.

"Did I meet with people that were Russian? I'm sure, I'm sure I did," he said. "But none that were set up. None that I can think of at the moment. And certainly none that I was representing the campaign in any way, shape or form."

Asked at that time whether he had ever discussed government policies related to Russia, the younger Trump replied "A hundred per cent no".

The Trump Tower meeting was not disclosed to government officials until recently, when Kushner, who is also a senior White House aide, filed a revised version of a form required to obtain a security clearance.

The Times reported in April that he had failed to disclose any foreign contacts, including meetings with the Russian ambassador to the United States and the head of a Russian state bank. Failure to report such contacts can result in a loss of access to classified information and even, if information is knowingly falsified or concealed, in imprisonment.

Kushner's advisers said at the time that the omissions were an error, and that he had immediately notified the FBI that he would be revising the filing. They also said he had met with the Russians in his official transition capacity as a main point of contact for foreign officials.

In a statement Saturday, Kushner's lawyer, Jamie Gorelick, said: "He has since submitted this information, including that during the campaign and transition, he had over 100 calls or meetings with representatives of more than 20 countries, most of which were during transition. Mr. Kushner has submitted additional updates and included, out of an abundance of caution, this meeting with a Russian person, which he briefly attended at the request of his brother-in-law Donald Trump Jr As Mr. Kushner has consistently stated, he is eager to cooperate and share what he knows."

Kushner's lawyers addressed questions about his disclosure but deferred to Trump Jr on questions about the meeting itself.

Manafort, the former campaign chairman, also recently disclosed the meeting, and Trump Jr's role in organising it, to congressional investigators who had questions about his foreign contacts, according to people familiar with the events.

A spokesman for Manafort declined to comment. Veselnitskaya did not immediately respond to questions including whether she had discussed the meeting with anyone in the Russian government.

Because Trump Jr does not serve in the administration and does not have a security clearance, he was not required to disclose his foreign contacts. Federal and congressional investigators have not publicly asked for any records that would require his disclosure of Russian contacts.

It is not clear whether the Justice Department was aware of the meeting before Kushner disclosed it recently. Neither Kushner nor Manafort was required to disclose the content of the meeting in their government filings.

During the campaign, Trump Jr served as a close adviser to his father, frequently appearing at campaign events. Since the president took office, the younger Trump and his brother, who have worked for the Trump Organisation for most of their adult lives, assumed day-to-day control of their father's real estate empire.

But a quick internet search would have revealed Veselnitskaya as a formidable operator with a history of pushing the Kremlin's agenda. Most notable is her campaign against the Magnitsky Act, which provoked a Cold War-style, tit-for-tat row with the Kremlin when President Barack Obama signed it into law in 2012.