Updated

Senate Judiciary Committee Chairman Chuck Grassley is calling for the appointment of a special counsel to investigate the Obama-era Uranium One deal, amid new revelations about the arrangement that have spurred fresh congressional probes.

Grassley, R-Iowa, tweeted late Tuesday, calling for the Justice Department to appoint an independent counsel to investigate the deal.

“Whoever in DOJ is capable w authority to appoint a special counsel shld do so to investigate Uranium One 'whoever' means if u aren’t recused,” Grassley tweeted.

His message may have been a reference to Attorney General Jeff Sessions -- who recused himself from the investigation into Russia's election meddling and potential collusion with Trump associates -- or Deputy Attorney General Rod Rosenstein. Rosenstein is overseeing the Russia probe, but as a U.S. attorney reportedly helped supervise a bribery probe into a subsidiary of the same Russian firm involved in the Uranium One deal.

The deal, which was covered extensively in 2015, concerns the 2010 approval of the sale of Canadian mining company Uranium One to Russia’s Rosatom nuclear company. The U.S. was involved because the sale gave the Russians control of part of the uranium supply in the U.S.

The Hill reported, however, that the FBI had evidence as early as 2009 that Russian operatives used bribes, kickbacks and other dirty tactics to expand Moscow’s atomic energy footprint in the U.S., related to a subsidiary of the same Russian firm. Republican lawmakers on Capitol Hill quickly started asking questions about how the deal was approved the following year by an inter-agency committee.

HOUSE REPUBLICANS LAUNCH NEW PROBES INTO OBAMA-ERA URANIUM ONE DEAL, FBI HANDLING OF CLINTON CASE

In addition to Grassley’s calls for a special counsel investigation, House Republicans on Tuesday launched new probes into several Obama-era controversies, including administration’s approval of the deal that gave Russians partial control over American uranium reserves.

Chairman of the House Intelligence Committee Devin Nunes, R-Calif., said his committee would not “jump to any conclusions,” but would “try and get the facts.”

Rep. Ron DeSantis, R-Fla., threatened to use his subpoena power to get access to a former FBI informant in the case who apparently has not yet been released from a non-disclosure agreement. U.S. government officials have told Fox News that senior Justice Department officials are in deliberations over providing the FBI informant to Congress.

But while congressional probes and subpoena power could undercover more details, the FBI informant’s attorney, Victoria Toensing, echoed Grassley’s calls for a special counsel.

REPUBLICANS SEE TABLES TURNED AS DEMS FACE FRESH RUSSIA CONTROVERSIES

“This cries out for a special counsel,” Toensing said on Fox News' “Hannity” Tuesday night. “Congressional committees are fine, but this is a criminal investigation and Jeff Sessions isn’t ever going to feel comfortable appointing that, and Rod Rosenstein is recused because he was the U.S. attorney.”

Toensing added that while Sessions can technically appoint a special counsel, he likely was “not going to be comfortable doing it.”

“He ought to get somebody in here and get this off their hands,” Toensing said.

Fox News' Judson Berger contributed to this report.