The United States plans to scrutinise the Clintons' charitable foundation and a uranium deal.
The US Department of Justice already directed the prosecutors through a letter to launch an inquiry into the Clinton Foundation and the Uranium One sale.
But Attorney General Jeff Sessions told a Senate hearing there is currently no basis for Republican calls to appoint a special counsel to investigate.
The issue is a longstanding political grievance of President Donald Trump.
A BBC report says, Democrats have called Uranium One a "massive diversion" from the investigations dogging Trump's presidency.
His aides are currently the focus of inquiries by a special counsel and congressional committees into whether they colluded with alleged Kremlin attempts to sway last year's US presidential election.
