WASHINGTON, July 19 (Xinhua) -- Donald Trump Jr., Jared Kushner, and former Trump campaign manager Paul Manafort are scheduled to appear before U.S. Senate committees next week.

Their hearings are part of the ongoing probes into a possible collusion between the Russian government and the Trump campaign in the 2016 presidential election.

Kushner, son-in-law of U.S. President Donald Trump and a senior White House adviser, intends to testify in a closed-door hearing of the Senate Intelligence Committee on Monday, July 24, his attorney confirmed in a statement on Wednesday.

"He has been and is prepared to voluntarily cooperate and provide whatever information he has on the investigations to Congress," said Abbe Lowell representing Kushner.

"He appreciates the opportunity to assist in putting this matter to rest," Lowell said.

The Senate Judiciary Committee said on Wednesday that it had called Trump's eldest son, Trump Jr., and his then-campaign manager Manafort to testify before a panel on July 26.

The requests for their appearance before Senate lawmakers were reportedly received on late Wednesday. Neither Trump Jr. nor Manafort has announced an intention to testify so far.

The three men have been repeatedly linked together for attending a meeting with a Russian lawyer in the hope of getting hands on previously-promised "damaging information" about Trump's then-opponent, Democratic presidential candidate Hillary Clinton.

The eight-person meeting, which took place on June 9, 2016 at Trump Tower in New York, also involved a Russian-born American lobbyist, a senior executive of a Russian real estate developer, an interpreter, and a British music publicist who proposed and later arranged the meeting via emails with Trump Jr.

The U.S. intelligence community alleged that Russia meddled in the U.S. presidential race last year and there were connections between the Russian government and the Trump campaign. A federal special counsel and several congressional panels are investigating these allegations.