In a letter sent Thursday to Senate Judiciary Committee Chairman Senator Chuck Grassley (R-IA), Senator Chris Coons (D-DE) called for an investigation into whether Donald Trump Jr. lied when he told the Senate Judiciary Committee that he did not know, aside from Russia, about the Trump campaign's involvement with foreign governments and foreign nationals.

"I am writing to you because I am deeply concerned that, based on new information we learned this week, Donald Trump Jr. provided false testimony to the Senate Judiciary Committee, and I would like to renew my request that he be called to return and appear before the full committee to testify in an open hearing," Coons wrote.

Coons highlights the following exchanges between Trump Jr. and the Senate Judiciary Committee in particular, which took place on September 7, 2017:

Q: We've talked a lot about Russia. So I have some broader questions about other foreign governments. Did other foreign governments offer or provide assistance to the Trump campaign?

A: None that I'm aware of.

Q: Did other foreign nationals offer or provide assistance to the Trump campaign?

A: No.

Q: Did you directly or indirectly seek foreign government or foreign nationals['] assistance for the Trump campaign?

A: No.

Q: Are you aware of anyone else seeking foreign government or foreign nationals['] assistance for the Trump campaign?

A: I'm not.

Q: Did you ever tell anyone that you or the Trump campaign would be receptive to offers of assistance from foreign governments or foreign nationals?

A: No.

Coons said that information in recent news reports contradicts Trump Jr.'s September 2017 testimony. A meeting, first reported by The New York Times last weekend, was held at Trump Tower. Coons lists all of the attendees in his letter to Grassley:

This testimony is contradicted by multiple recent news reports that three months before the election, Mr. Trump Jr. and campaign adviser Stephen Miller met with George Nader, an emissary for the crown princes of the United Arab Emirates and Saudi Arabia; Joel Zamel, an Israeli social media specialist linked to Israeli intelligence and the Emirati royal court; and Erik Prince, a campaign donor and private security contractor with business in the Middle East.

Coons notes that "attendees reportedly offered assistance to Donald Trump's presidential campaign on behalf of foreign governments and foreign nationals." It's a crime for foreign governments or nationals to be involved in U.S. elections.

"It is fundamental to the integrity of the Senate Judiciary Committee that testifying witnesses must be truthful," Coons continues. "Material false statements to Congress are criminal and punishable under 18 U.S.C. § 1001."

A copy of the letter is provided below.

Trump Jr. has not commented on the development even as the news trended on social media.

"Is everyone processing the fact that over the past 72 hours three major-media reports have established that Donald Trump Jr., Erik Prince, and Roger Stone all lied to Congress, a federal felony?" wrote legal and political analyst Seth Abramson.

"Lying to Congress is a crime, even if you are not under oath," commented political watchdog group Citizens for Responsibility and Ethics in Washington (CREW).

If Trump Jr. did, in fact, lie to Congress, "that's a crime," wrote David Corn, the D.C. Bureau Chief of Mother Jones.

Trump Jr. came under fire last year for revealing that he met with a Russian lawyer during the 2016 presidential campaign. An intermediary for the lawyer promised damaging information about Hillary Clinton, the Democratic opponent. Trump Jr.’s emails––”If it’s what you say I love it especially later in the summer,” he wrote––contradict months of denials by the Trump administration of any collusion with Russian operatives.

Trump Jr. and the others who attended the meeting (including the president’s son-in-law and adviser Jared Kushner and former campaign chairman Paul Manafort) claimed nothing came of it, insisting they met with lawyer Natalia Veselnitskaya to discuss issues related to U.S. sanctions against Russia and the adoption of Russian children by Americans.