White House adviser Jared Kushner ought to testify under oath in an open session of the Senate Intelligence Committee, Sen. Ron Wyden (D-Ore.) said Monday.

President Donald Trump’s son-in-law faced questions from committee staff behind closed doors on Monday about his contacts with Russian citizens and officials. He is scheduled to answer more questions about the matter during a similar meeting with the House Intelligence Committee on Tuesday.

In a statement released Monday, Kushner said he “did not collude, nor know of anyone else in the campaign who colluded, with any foreign government.”

Wyden said Monday that Kushner’s 11-page written statement about four meetings he had with Russians during last year’s presidential campaign and during the Trump administration’s transition, which he failed to disclose on a security clearance form, “raises far more questions than it answers.”

“He has an obligation to be transparent with all relevant documents to back up his claims,” the Senate Intelligence Committee member said in a statement.

“More broadly, Kushner has repeatedly concealed information about his personal finances and meetings with foreign officials,” he added. “There should be no presumption that he is telling the whole truth in this statement.”

Wyden noted Kushner’s statement was likely written with the help of a “clever lawyer” and may have been carefully crafted in the way it described the meetings.

Kushner will reportedly not be under oath during his scheduled appearances before the committees. Under federal law, however, it is still illegal to lie to Congress.

Donald Trump Jr. and former Trump campaign chairman Paul Manafort, who are scheduled to meet with the Senate Intelligence Committee behind closed doors on Wednesday, will also not be under oath when they testify.

“That’s not good enough,” Sen. Al Franken (D-Minn.) said Sunday. “It should be under oath.”

Sen. Joe Manchin (D-W.Va.) said the investigation into Russia’s interference of last year’s presidential election ought to be “as transparent as possible.”

“I think the public has a right to know the facts as we know them and if it’s not endangering any of the assets we have with our intelligence community and how we secure our nation and keep it safe ― if those things aren’t in jeopardy ― then we should have it as transparent as possible,” he said Monday during an interview on MSNBC.