On the day Jared Kushner is due to appear before a Senate Intelligence Committee, President Donald Trump’s son-in-law and senior White House adviser was involved in a multi-million dollar deal with a Soviet-born real estate tycoon and diamond merchant.

The Guardian's investigative report “established a series of overlapping ties and relationships involving alleged Russian money laundering, New York real estate deals and members of Trump’s inner circle.”

It also includes a 2015 sale of part of a building in Manhattan involving Kushner and Lev Leviev, a business partner of the Russian-owned Prevezon Holdings that was at the center of a multimillion-dollar lawsuit launched in March 2017 over money laundering charges.

Questions on this deal are likely to figure along with others regarding his involvement with Russian citizens and officials when he testifies before the Congress over an allegation of Russia’s interference in last year’s presidential election.

In a statement released Monday ahead of Kushner's appearance before the committee, he said he had "no additional contacts" with the Russian government representatives beyond those that have already been publicly disclosed. 

"I did not collude, nor know of anyone else in the campaign who colluded, with any foreign government. I had no improper contacts. I have not relied on Russian funds to finance my business activities in the private sector," Kushner said in the statement.

READ: Is Jared Kushner Becoming The Center Of Russia Investigation?

Kushner’s appearance before a closed session of Senate Intelligence Committee on Monday and the House of Representatives Intelligence Committee on Tuesday was preceded by media scrutiny of Trump family real estate deals and Russia money interests.

According to the New York Times, Special Counsel Robert Mueller has expanded his probe to look into real estate deals involving Trump Organisation as well as Kushner’s finances.

In his New York Times interview on July 19, Trump had warned Mueller he would be “crossing a red line” by investigating his family’s violation.

“I think that’s a violation. Look, this is about Russia," the president said.

Top question in the hearing is likely to be Kushner's attendance for the June 2016 meeting at the Trump Tower arranged by his brother-in-law Donald Trump Jr.

Four Russians led by lawyer Natalia Veselnitskaya, believed to be having Kremlin connections, met Trump Jr., Paul Manafort, and Kushner to provide damaging information about former Secretary of State Hillary Clinton.

Investigators are likely to ask Kushner why he didn't disclose the encounter on his security clearance application, as required by law.

READ: Jared Kushner Wants To Clear His Name Over Russia Meetings

Also on the table would be the report that Kushner had tried to set up a back channel with Russian official and business leaders during the campaign and transition period.

In May, The Washington Post reported Kushner “allegedly proposed to the Russians setting up a secret communications channel using secure diplomatic facilities.”

According to an NBC report, members of the Russia probe were looking into “whether Kushner had attempted to create the channel so he could find somebody in Moscow to buy the massively expensive 41-story tower at 666 Fifth Avenue,” which Kushner Companies bought in 2007 for $1.8 billion , and on which it has been losing money since then.

“We have a lot of ground to cover,” Rep. Adam Schiff, the top Democrat on the House Intelligence Committee, told CBS’ “Face the Nation” on Sunday. Schiff said the panel could ask Kushner to testify further if still has further questions after Tuesday. “We expect this is just going to be the first interview,” Schiff said.

Meanwhile,  Trump Jr. and Manafort have been called to testify before the Senate Judiciary Committee on Wednesday.