Donald Trump Jr.
Donald Trump Jr. said he met a woman in June 2016 — who turned out to be a Kremlin-connected lawyer. In this photo, Trump, Jr. attends the 139th White House Easter Egg Roll on the South Lawn of the White House in Washington, D.C., April 17, 2017. Getty Images

Hours after the New York Times reported about Donald Trump Jr.'s meeting with a Russian lawyer who promised to provide helpful information to his father's presidential campaign, ethics lawyer Richard Painter — who has previously worked under former President George W. Bush — criticized Trump Jr. for the meeting, and said it "borders on treason."

"This was an effort to get opposition research on an opponent in an American political campaign from the Russians, who were known to be engaged in spying inside the United States," Painter said Sunday during an interview on MSNBC.

"We do not get our opposition research from spies, we do not collaborate with Russian spies, unless we want to be accused of treason."

Painter also asserted former President Bush would not have allowed such a meeting to take place. "If this story is true, we’d have one of them if not both of them in custody by now, and we’d be asking them a lot of questions," he said, referring to the presence of President Donald Trump’s then-campaign manager Paul Manafort and Trump's son-in-law Jared Kushner at the meeting. "This is unacceptable. This borders on treason, if it is not itself treason."

Trump's eldest son admitted in a statement he was asked to meet Russian attorney Natalia Veselnitskaya in June 2016, the New York Times report claimed.

The meeting was first reported by the Times in an article published Saturday. The report said the meeting was also attended by Manafort and Kushner, and it took place just weeks after Trump secured his GOP nomination. Citing several sources, the Times reported Sunday that Trump Jr. was promised damaging information about Hillary Clinton before agreeing to meet with the Kremlin-connected lawyer.

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However, Trump Jr. claimed in a statement Sunday the lawyer did not provide any information related to the election campaign and that they discussed about Russian adoption.

"I was asked to have a meeting by an acquaintance I knew from the 2013 Miss Universe pageant with an individual who I was told might have information helpful to the campaign. I was not told her name prior to the meeting. I asked Jared and Paul to attend, but told them nothing of the substance. We had a meeting in June 2016. After pleasantries were exchanged, the woman stated that she had information that individuals connected to Russia were funding the Democratic National Committee and supporting Ms. Clinton. Her statements were vague, ambiguous and made no sense. No details or supporting information was provided or even offered. It quickly became clear that she had no meaningful information. She then changed subjects and began discussing the adoption of Russian children and mentioned the Magnitsky Act."

The remarks came a day after he had given a different explanation about what was discussed during the meeting. He said the meeting focused solely on the Russian adoption issue, according to the Times article.

"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 a campaign issue at the time and there was no follow up."

Referring to the meeting, a spokesman for the president's legal team, Mark Corallo, was quoted as saying by Fox News: "The president was not aware of and did not attend the meeting."

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The news of Trump Jr.’s meeting with the Russian lawyer came a day after his father attended the G-20 summit Friday where he met with Russian President Vladimir Putin for the first time.

On Sunday, Trump took to Twitter and said he strongly pressed Putin over the allegations regarding Moscow's meddling into the presidential election. Russian president vehemently denied the claims. Following the meeting, Trump said it was time to move forward in working constructively with Russia. He announced the two countries may also get involved in a joint cyber security effort, which Trump later said, can’t happen.