The move follows unsubstantiated charges by President Donald Trump and his allies that his predecessor’s administration spied on Trump and improperly "unmasked" the identities of his associates during the 2016 presidential campaign and transition.
Current and former senior U.S. intelligence officials who have reviewed the documentation dispute those claims by the president.
In September, the U.S. Justice Department said in a court filing that it had no evidence to support the president’s claim that President Barack Obama ordered surveillance of his Trump Tower campaign headquarters.
In a Nov. 30 letter sent to Representative Devin Nunes, Republican chairman of the House Intelligence Committee, and other top lawmakers, the Director of National Intelligence Dan Coats said the new unmasking policy is due by Jan. 15.
Nunes was among the first to charge that U.S. intelligence agencies collected information on Americans involved in Trump’s transition team. A Nunes spokesman declined comment.
Coats wrote that the new policy will reinforce existing procedures that "make clear that IC (intelligence community) elements may not engage in political activity, including dissemination of U.S. person identities to the White House, for the purpose of affecting the political process of the United States."