WASHINGTON – President Trump's lawyer sought to distance his client Sunday from an increasingly scrutinized meeting Donald Trump Jr. took with Russians who may have links to the Kremlin – even as he insisted the meeting was perfectly appropriate during a U.S. presidential campaign.

The attorney, Jay Sekulow, said the president did not know about the June 2016 meeting his oldest son took with Russian attorney Natalia Veselnitskaya. The younger Trump released emails earlier this week showing he sought damaging information about Hillary Clinton's campaign even though he was told it would come from the Russian government.

"There's not a violation of the law," attorney Jay Sekulow told Fox News Sunday, one of a string of Sunday show interviews with the high-profile member of the president's legal team.

Just three days after Trump Jr., said Tuesday that he released the email correspondence, a series of news reports showed there was more to the story: A Russian-American lobbyist, Rinat Akhmetshin, who has been described as a former Soviet military counterintelligence office, was also in the meeting. Akhmetshin told the New York Times that a translator was also in the meeting.

With controversy brewing, members of Congress said they want testimony from Donald Trump Jr. and others involved in the June 2016 meeting that also included former Trump campaign chairman Paul Manafort, and Jared Kushner, the president's son-in-law and now a White House senior adviser.

"Real evidence is coming forward that can't be ignored," said Rep. Adam Schiff, D-Calif., the top Democrat on the House Intelligence Committee, speaking on ABC's This Week.

He described the meeting as the clearest example yet of possible collusion between the Trump campaign and Russians who sought to interfere in last year's election by hacking Democrats close to nominee Hillary Clinton.

No meetings w/ Russians
Yes, meetings
No collusion
We tried to
It's not illegal
Everybody does it

I didn't know.

— Adam Schiff (@RepAdamSchiff) July 16, 2017

Key Democrats also pointed out that Trump Jr. and other officials keep changing their stories about the meeting, including the number of people who attended.

“Almost every week we find another thread that we have to pull on," said Sen. Mark Warner, D-Va., top Democrat on the Senate Intelligence Committee, told CNN's State of the Union, one of the panels investigating possible collusion between the Trump campaign and Russia.

Warner said he would seek testimony from Trump Jr. and Kushner, but was unsure whether the Russians would agree to cooperate with the congressional committee.

During his Sunday show appearances, Sekulow stressed that the Russians did not provide any information about Clinton in any case, but only tried to lobby the Trump team about sanctions on Russia.

Trump Jr.'s eagerness to take the meeting reflected standard "opposition research," Sekulow said. He also argued that "collusion" is a political term, not a legal term.

"The fact is there is no collusion statute," Sekulow said.

Sekulow also told ABC, "if this was nefarious, why'd the Secret Service allow these people in?" The service's mission is to protect the president, not to monitor meetings.

Legal analysts have said Trump Jr. may have breached campaign finance laws that forbid foreign contributions – and a special counsel is conducting a criminal investigation into possible collusion between Trump associates and Russia during the campaign.

As for the president himself, Sekulow said he did not know about the meeting or any other Russian efforts to influence the election.

"We have no notification of any investigation going on of the President of the United States," Sekulow said on NBC's Meet The Press.

Trump himself, spending the weekend at his golf club in New Jersey, spent part of the day again criticizing news coverage of his son, and attacking his 2016 opponent.

"Hillary Clinton can illegally get the questions to the Debate & delete 33,000 emails but my son Don is being scorned by the Fake News Media?" Trump said in one post.