Senate Judiciary Chairman Chuck Grassley, R-Iowa, is demanding the Justice Department allow a former confidential informant to the FBI to speak to Congress, even though the informant is still under a non-disclosure agreement.

Media reports indicate the FBI had evidence Russian officials were working bribery, extortion, and money laundering schemes to expand Putin's atomic energy pursuits inside the U.S., including the partial sale of Uranium One, a Canadian mining company. That information came before the Obama administration approved a 2010 deal that gave Moscow control of significant amounts of America's uranium supply.

The confidential informant Grassley wants to hear from apparently has first-hand knowledge of the extent to which Moscow compromised an American uranium trucking firm.

The report by the Hill also claims eyewitness accounts and documents back up a story that Russian nuclear officials worked to move millions of dollars to the U.S., and then to former President Bill Clinton's charitable foundation at a time when Secretary of State Hillary Clinton "served on a government body that provided a favorable decision to Moscow, sources told The Hill."

"The Executive Branch does not have the authority to use non-disclosure agreements to avoid Congressional scrutiny," Grassley wrote. "If the FBI is allowed to contract itself out of Congressional oversight, it would seriously undermine our Constitutional system of checks and balances. The Justice Department needs to work with the Committee to ensure that witnesses are free to speak without fear, intimidation or retaliation from law enforcement."

Grassley's letter to the Justice Department also asks for a copy of the non-disclosure agreement the informant signed with the FBI.

In a Wednesday hearing of the Senate Judiciary Committee, Grassley said, "This committee has an obligation to get to the bottom of this issue."

The chairman also fired off letters in the previous week to ten federal agencies in an attempt to find out if the committee that approved the uranium deal was aware of the FBI investigation.

Hillary Clinton was secretary of state and a part of the Committee on Foreign Investment in the United States when the committee approved the partial sale of Uranium One, which resulted in Russia then having control over roughly 20 percent of the U.S. uranium supply.