Also Thursday, the Justice Department released a heavily blacked out page from Attorney General Jeff Sessions' security clearance application in response to a government watchdog group's lawsuit. "What I'm saying is that we have to protect ourselves no matter who it is".
Accusations Moscow meddled in the election and colluded with the Trump campaign have dominated Trump's first months in office.
In a recent interview, Veselnitskaya denied having discussed Hillary-related issues with Trump Jr. during the meeting.
Multiple agencies in the USA intelligence community have previously concluded that Russia's President Vladimir Putin directed a co-ordinated effort to interfere in the 2016 U.S. presidential election. Are you telling me this is a coincidence?
Futerfas told NBC he spoke with the man who accompanied Veselnitskaya to the meeting, and that the person is a USA citizen who told him specifically "he was not working for the Russian government, and in fact laughed when I asked him that question".More news: Presidential poll: Naveen rules out possibilities of cross voting by BJD leaders
Asked at his weekly news conference about Grassley's letter and whether Trump Jr. should testify, House Speaker Paul Ryan didn't object to the move.
In Washington, Sen. Charles Grassley (R-IA), chairman of the Senate Judiciary Committee, sent a letter to the younger Trump asking him to testify about his June 2016 meeting with Russian lawyer, Natalia Veselnitskaya.
The emails between Trump Jr. and a publicist show that the president's son believed Veselnitskaya was a lawyer for the Kremlin who was offering to provide damaging information about his father's opponent, then-Democratic nominee Hillary Clinton.More news: Dow Jones Closes at Record High for Second Straight Day
Asked on Wednesday if he knew his son was meeting with lawyer Natalia Veselnitskaya in June previous year, the president said: "No, that I didn't know until a couple of days ago when I heard about this".
Donald Trump Jr. has said he is willing to testify voluntarily, but Grassley said he would be subpoenaed if need be. We've got to ask about this.
A friend of Trump Jr.'s who helped set up the meeting had described Veselnitskaya to him in emails as a Russian government lawyer.More news: Anadarko Petroleum Corporation (APC) Shares Bought by Loomis Sayles & Co. LP
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