U.S. President's son, Donald Trump Jr., has added a lawyer with congressional experience to his legal team, the lawyer told reporters on Sunday.

Trump Jr. has hired Karina Lynch of the law firm Williams and Jensen, to his legal team investigating the Russians interference in the 2016 U.S. Election. She did not respond to queries about what her role in the team would be.

Trump Jr. also hired Alan Futerfas as a lawyer after reports detailed meetings last year between Trump Jr. and a Russian lawyer.

Trump Jr., his father's former campaign manager Paul Manafort and Jared Kushner, the president's son-in-law and one of his senior advisers, met with Russian lawyer Natalia Veselnitskaya in June 2016. That meeting was held in Trump Tower in New York after the lawyer offered damaging information about Democratic presidential candidate Hillary Clinton.

A federal special counsel and several congressional panels are investigating allegations by U.S. intelligence agencies that Russia meddled in the 2016 U.S. presidential election and potential connections between Russian officials and the Trump campaign.

Moscow has denied any interference, and Trump says his campaign did not collude with Russia.