WASHINGTON — President Trump’s eldest son cast his meeting with a Russian lawyer last year as simply an opportunity to learn about Hillary Clinton’s “fitness, character or qualifications,” insisting Thursday to Senate investigators behind closed doors that he did not collude with Russia to hurt her campaign against his father.

Donald Trump Jr.’s description of the June 2016 meeting at Trump Tower in New York, delivered in a statement at the outset of a Senate panel’s staff interview, provided his most detailed account yet of an encounter that has drawn close scrutiny from Congress and investigative special counsel Robert Mueller.

He tried to dismiss concerns about a comment he made in emails leading up to the meeting that has attracted controversy. He said he was just being polite and “colloquial” when he emailed “I love it” to Rob Goldstone, the publicist who was setting up the meeting with a Russian who was said to have election-season dirt on Clinton.

Trump Jr. said it was “simply a colloquial way of saying that I appreciated Rob’s gesture.”

Thursday’s interview was the first known instance of Trump Jr. giving his version of the meeting in a setting that could expose him to legal jeopardy. It’s a crime to lie to Congress.

Multiple congressional committees and Mueller’s team of prosecutors are investigating whether the Trump campaign coordinated with Russia to influence the outcome of the election. A grand jury used by Mueller as part of his investigation has already heard testimony about the meeting, which besides Trump Jr., included the president’s son-in-law, Jared Kushner, and his then-campaign chairman, Paul Manafort.

Trump Jr. spoke to the committee for about five hours, leaving at midafternoon out of view of reporters. In a statement released afterward, he appeared to suggest he would not testify publicly before the committee, saying he trusted that “this interview fully satisfied” the panel’s inquiry.

In July, the committee’s chairman, Republican Chuck Grassley of Iowa, said he wanted Trump Jr. to appear at a public hearing, though in recent days he’s declined to say whether that will still happen. California Sen. Dianne Feinstein, the top Democrat on the panel, said Wednesday that she and Grassley had agreed in July to subpoena Trump Jr. if he wouldn’t appear willingly in public.

Trump Jr. and the Senate Judiciary Committee negotiated for him to appear privately Thursday.