If Trump Jr agrees to appear before the judiciary committee, he would be the highest member of the president's inner circle of relatives and White House aides to testify in Congress about the Russia allegations.
US President Donald Trump's eldest son and his former campaign chairman have been given approval by a US special counsel to testify publicly to Congress as part of investigations into Russian meddling in the 2016 election, top Democrat on the Senate Judiciary Committee said.
Senator Dianne Feinstein said on Tuesday special counsel former FBI director Robert Mueller said Donald Trump Jr and Paul Manafort, who was the campaign manager from March to August, were free to speak to the committee.
Mueller is investigating allegations by US intelligence agencies that Russia interfered to help Trump win the presidency and possible collusion between Moscow and the Republican's campaign.
But Russia denies meddling in the campaign, and Trump says there was no collusion.
If Trump Jr were to appear before the judiciary committee, he would be the highest member of the president's inner circle of relatives and White House aides to testify in Congress about the Russia allegations.
Several congressional panels have investigations open.
The allegations have dominated Trump's first six months in office.
Meeting in Trump Tower
Trump Jr, who runs the Trump family business, released emails last week in which he eagerly agreed in June 2016 to meet a woman he was told was a Russian government lawyer who might have damaging information about Democratic election rival Hillary Clinton as part of Moscow's support for his father's campaign.
The meeting in Trump Tower in New York appears to be the most tangible evidence of a connection between Trump's campaign and Russia, investigators in Congress have said.
Judiciary Committee Chairman Charles Grassley has said he would coordinate with Mueller to ensure that any witnesses the panel brings would not conflict with Mueller's criminal investigation.
Feinstein said the committee planned for the testimony to be part of a broader hearing scheduled for Wednesday but has now been postponed.
She could not confirm whether the hearing would take place next week.
The Miss Universe connection
A representative of the Russian developer who partnered with President Donald Trump to bring the Miss Universe pageant to Moscow was the eighth person at the Trump Tower meeting arranged by Donald Trump Jr, a lawyer for the developer said Tuesday.
Ike Kaveladze attended to help translate at the meeting with Trump Jr, the Russian lawyer Natalia Veselnitskaya and others, attorney Scott Balber told The Washington Post and CNN.
Balber told the media outlets that Kaveladze works for Moscow-based developers Aras Agalarov and his son, Emin, an Azerbaijani-Russian pop star, and was there to represent them. The father and son, who worked with Trump on the pageant in 2013, were named in the emails that promised damaging information on Hillary Clinton.
In an online profile, Kaveladze lists himself as a vice president of Russia-based Crocus Group, Aras' firm, and says in a separate LinkedIn profile that he handled tax preparation for the company.
Balber represented Trump himself in the New York businessman's 2013 lawsuit against comedian television host Bill Maher, demanding the $5 million Maher offered to give to charity if Trump could prove his father is not an orangutan.
Kaveladze was asked to go to the meeting with the understanding that he would be a translator for Veselnitskaya, only to find she had brought her own translator with her, Balber told CNN.
Balber said he also represents the Agalarovs. Balber said Mueller's investigators have not interviewed his client or made contact about the Agalarovs.
In addition to Trump Jr, Veselnitskaya, her translator, and Kaveladze, the meeting was attended by Trump son-in-law Jared Kushner, Manafort, publicist Rob Goldstone and Russian-American lobbyist Rinat Akhmetshin.
Anatoli Samochornov was identified as Veselnitskaya's translator in multiple media reports.
In Moscow, Russia said it reserved the right to retaliate against the US after a meeting in Washington ended without an agreement to return Russian diplomatic property the US had seized.
Trump's predecessor president Barack Obama ordered the seizure of two Russian diplomatic compounds in New York and Maryland and the expulsion of 35 Russian diplomats in December over what he said was their involvement in hacking the US election campaign.