Washington (CNN) House Republicans announced a probe into the circumstances surrounding the sale of a uranium mining company to Russia's Atomic Energy Agency, Rosatom , that was approved by the Obama administration in 2010.

The deal had to be approved by the Committee on Foreign Investment in the United States, a committee that is composed of representatives from several US government agencies, including the State Department, which at the time was led by Secretary Hillary Clinton.

New questions have been raised by Republican lawmakers in light of reporting by The Hill that while the uranium deal was being reviewed and approved, the FBI was in the beginning stages of a racketeering and extortion investigation into a US subsidiary of Rosatom.

President Donald Trump seized on the new reporting, telling reporters on Wednesday that he feels the newly announced investigations into the sale are "Watergate, modern age."

"I think the uranium sale to Russia, in the way it was done, so underhanded with tremendous amounts of money being passed, I actually think that is Watergate, modern age," he said.

The Hill reporting raises questions about whether decision-makers on the uranium deal, including members of Congress, were informed of the racketeering investigation that was ongoing. Further, the Hill cites sources indicating that Russian nuclear officials routed millions of dollars to the US that were designed to benefit the Clinton Foundation at the same time the deal was approved. The Hill does not indicate there's any evidence to show that Clinton was influenced by this.

The FBI criminal probe resulted in the sentencing of Vadim Mikerin, an executive at Tenex (a subsidiary of Rosatom), to a 48-month prison sentence for conspiracy to commit money laundering. Mikerin pleaded guilty for his role in a bribery scheme where Russian interests had compromised an American uranium trucking firm with bribes and kickbacks.

Court documents connected with the case reviewed do not reference donations to the Clinton Foundation, nor attempts by US or Russian interests to influence the Uranium One deal decision.

Since these allegations have resurfaced in the wake of recent reporting, Clinton and members of her staff have disputed accusations that anything improper occurred surrounding the approval of the Uranium One deal.

Clinton said in an interview with C-SPAN this week that any accusations that she was bribed to approve the deal were "baloney" and that they had been "debunked repeatedly."

Jake Sullivan, former director of Clinton's State Department Policy Planning Office, told CNN's Wolf Blitzer in an interview last week that "there was really nothing to" the allegations of Clinton influencing the decision based on donations made to the Clinton Foundation. Sullivan said that Clinton did not participate in the CFIUS decision, since the approval went through a "nine-agency committee ... there was nothing here other than a normal process."

Former Justice Department national security attorney Joshua Geltzer said "it's not unusual for a CFIUS review to be handled by career civil servants" as opposed to the agency head, like Clinton, on the committee. Geltzer served during the Obama administration and advised the Justice Department's leadership on CFIUS matters, but did not join the administration until 2013 after this deal was made.

"While ultimate approval for a particular department or agency's position on a CFIUS matter may come from its political leadership, the bulk of the analysis that informs a recommendation for that position tends to be produced by the subject-matter experts," Geltzer said.

The timing of the FBI probe is also a key question, as is when officials who approved the uranium deal knew about it. According to court records, the scheme first became known to federal investigators in 2009 when an American businessman was recruited to assist, and then alerted the FBI. That businessman became an informant for the FBI and participated in the bribery plan, with the FBI's approval. But the FBI did not announce the indictment until it was unsealed in October 2014, four years after the Obama administration approved the uranium deal.

The timing is the key part of the investigation announced by House Intelligence Committee Chairman Devin Nunes Tuesday.

"One of the things that you know we're concerned about is whether or not there was an FBI investigation," Nunes said. "Was there a DOJ investigation? If so, why was Congress not informed of this matter?"

The FBI referred CNN to the court documents, and any additional inquiries to the Justice Department, which has not yet commented.

FBI investigations are typically not disclosed at the time they are ongoing, so it is possible that the government officials involved in approving the Uranium One deal were not aware of the criminal investigation at the time of the approval. CNN spoke with Ronald Hosko, assistant FBI director in charge of criminal cases at the time of the investigation, who said that he wasn't aware of the ongoing probe, saying it was handled on the counterintelligence side of the bureau. Counterintelligence investigations are some of the most closely held in the FBI. Former Rep. Mike Rogers, R-Michigan, who chaired the House Intelligence Committee at the time of the probe, also told The Hill that he was never informed about the FBI probe either.

The informant who played a crucial role in the FBI investigation is now trying to speak out, but his attorney says he is barred by a non-disclosure agreement the FBI made him sign. A law enforcement source familiar with the process said it is common for cooperating witnesses to sign non-disclosure agreements when the investigation involves national security concerns, as it did in this case. However, these agreements are typically narrowly written, and do not typically prevent individuals from speaking to Congress about what they learned in the ordinary course of business while simultaneously working as an informant, the source said. However, the source says the agreement would prevent any disclosure of information that was gleaned while working closely with federal investigators as it pertained to the investigation itself.

The informant's attorney tells CNN the informant has a lot of information about corruption that has not come out yet. In particular, the attorney maintains that while the FBI investigation was going on, FBI agents told the informant that President Barack Obama was being briefed on the probe, and that's why the informant was so stunned when the Uranium One deal was approved in 2010. Obama's representative declined to comment.

In addition to the probe announced by the House intelligence committee and the House oversight committee Tuesday afternoon, Senate Judiciary Committee Chairman Chuck Grassley has also written a letter calling on the Justice Department to lift the non-disclosure agreement preventing that informant from speaking to Congress. Grassley sent the letter to Attorney General Jeff Sessions on October 18. Grassley also sent a letter to the informant's attorney requesting an interview with the informant.

This article has been revised to correct the spelling of the Russian atomic energy agency, Rosatom.