His letter left open the possibility that, depending on what Huber's and the IG's reviews turned up, a second special counsel could be appointed.
Sessions further defended his decision to keep the matters formally under the jurisdiction of the Inspector General's Office (OIG), explaining that, unlike a special counsel, OIG publicizes misdeeds and damning communications that do not necessarily rise to the criminal level.
But Sessions has named a United States attorney to lead a review of the topics that the legislators had requested he explore.
"It is a shame that the inspector general has to devote resources to investigate a conspiracy theory as fact-free, openly political, and thoroughly debunked as the president's so-called 'FISA abuse, '" said New York Rep. Rep. Jerrold Nadler, the top Democrat on the House Judiciary Committee.
Sessions said he will rely on Huber's review to determine if a special counsel is needed.
The letter came amid congressional Republicans' requests that Sessions appoint a special counsel to look into the way the Federal Bureau of Investigation secured a warrant against Carter Page from the Foreign Intelligence Surveillance Court in 2016.
United States Attorney for Utah John Huber has been investigating whether the FBI abused its authority in surveilling a former top aide to then-GOP presidential nominee Donald Trump and whether federal officials should have probed deeper into allegations of Hillary Clinton's ties to the sale of us uranium rights to a Russian-controlled company.
Democrats view their concerns as unfounded and part of a possible ploy to distract from the work of special counsel Robert Mueller III, whom Deputy Attorney General Rod Rosenstein appointed to look into whether the Trump campaign coordinated with Russian Federation to influence the 2016 presidential election.
Remington files for bankruptcy in midst of school shooting protests
The company listed assets in the range of $500 million to $1 billion and liabilities in the range of $500 million to $1 billion. A likely buyer for Remington is someone who invests family money and does not need to answer to investors, the partner said.
Lawmakers reiterated their calls for a second special counsel even after Horowitz's announcement, noting that the inspector general's authority is limited in some respects.
Sessions addressed that issue in Thursday's letter, explaining how Huber and Horowitz will work in conjunction, and attempting to dispel the notion that the inspector general can not interview witnesses outside the department. Isn't the I.G.an Obama guy?
"We understand that the Department is not above criticism and it can never be that the Department conceals errors when they occur", he wrote in a letter to leading lawmakers.
Huber's appointment might allay some.
Sessions stopped short of appointing a special counsel to probe the claims, saying he would wait first for Huber's findings.
They added: "We expect that U.S. Attorney Huber, given his reputation, will conduct an independent and thorough investigation".
The attorneys said Albury "accepts full responsibility" for the alleged conduct.