Donald Trump Jr has released emails revealing his discussions about an offer of Russian information to "incriminate" Hillary Clinton.
The US President's eldest son used his Twitter account to publish correspondence about a meeting with a Russian lawyer, which is at the centre of a political row, in a move praised by his father.
In the email chain, Mr Trump Jr is shown in contact with music publicist Rob Goldstone to arrange to meet with Natalia Veselnitskaya at Trump Tower in New York, on 9 June last year.
The emails reveal Mr Trump Jr was in contact over an offer to provide the Trump presidential campaign with "official documents and information" that would "incriminate" Democratic rival Mrs Clinton and "her dealings with Russia".
The offer of "very high level and sensitive information" was described as "very useful to your father" by Mr Goldstone, who added it was "part of Russia and its government's support for Mr Trump".
The information was claimed to be from the "crown prosecutor of Russia" with Mr Trump Jr's meeting said to be with a "Russian government attorney".
In reply to the offer of "ultra sensitive" information on Mrs Clinton, Mr Trump Jr said: "If it's what you say I love it."
A White House spokeswoman said it is "ridiculous" to talk of perjury and treason in reference to contact with Russia.
She added the President is "frustrated" Russia continues to be an issue and Mr Trump would love to move on to other topics.
Mr Trump Jr has previously confirmed the meeting took place, which was also attended by the President's son-in-law Jared Kushner and Paul Manafort, the Trump campaign chief at the time.
Alleged links between the Trump campaign and Russia - along with Moscow's possible meddling in the US election - are currently the focus of a number of inquiries, including a wide-ranging probe by special counsel Robert Mueller, an ex-FBI chief.
Here's my statement and the full email chain4:00 PM - 11 Jul 201711,724 19,839 Donald Trump Jr.@DonaldJTrumpJr FollowDemocratic Senator Ron Wyden said the emails show the Trump campaign "sought to collude with a hostile foreign power to subvert America's democracy", although Republicans played down the revelations.
Democratic leader in the Senate, Chuck Schumer, called on Mr Trump Jr to hand over all documents related to contact with Russia.
The emergence of Mr Trump Jr's meeting on 9 June, first revealed by the New York Times, has prompted calls for the President's son to appear before a congressional committee.
In a statement also published on Twitter, Mr Trump Jr said he was releasing the emails in order to be "totally transparent".
|The meeting took place at Trump Tower in New York|
Mr Trump Jr had earlier mocked the "desperation" of the media and Democrats over the "nonsense meeting".
His publication of the emails followed Ms Veselnitskaya claiming she was asked to meet Mr Trump Jr by an unknown man.
She said she received a phone call and was asked if she knew damaging information about Mrs Clinton's campaign.
"All I knew was that Donald Trump Jr was willing to meet with me," she told the NBC Today show.
"It's quite possible that maybe they were looking for information. They wanted it so badly."
Ms Veselnitskaya, who is known for her work around adoption laws, told NBC that she had been lobbying against US sanctions on Russian officials but was not acting on behalf of the Kremlin.
Moscow has seconded those claims, saying in a statement that it had no connection with Ms Veselnitskaya .
Mr Goldstone said on Monday he had set up the meeting on behalf of his client Emin Agalarov, but that it ended up being "the most inane nonsense I've ever heard".
Mr Trump Jr said he had known Mr Agalarov, a singer from a billionaire family who once recorded a music video with the US President, since they staged the 2013 Miss Universe contest in Moscow.
Russia's foreign minister Sergei Lavrov claimed on Tuesday there is an "anti-Russian bias" in the US Congress, as he threatened "counter actions" against American diplomatic sanctions on Moscow.
He suggested former President Barack Obama's outgoing administration had aimed to "poison to a maximum US-Russian ties" and create a "trap" for Mr Trump late last year.