"For the part of the national security apparatus that I oversaw as DNI, there was no such wiretap activity mounted against the President-elect at the time, or as a candidate, or against his campaign," Clapper said Sunday morning on NBC's "Meet the Press."
Asked whether he could confirm or deny whether the FBI could have tapped Trump's phones under the Foreign Intelligence Surveillance Act, Clapper said, "I can deny it," adding that, to his knowledge, there was no court order to monitor any phones at Trump Tower.
Building on Clapper's remarks, a former senior official also told CNN on Sunday that he is not aware of any wiretaps on Trump's phones related to a criminal investigation by the Justice Department during the 2016 election.
Trump is asking Congress to look into whether the Obama administration abused its investigative powers during the 2016 election, White House press secretary Sean Spicer said in a statement Sunday.
The request came a day after the President took to Twitter to accuse former President Barack Obama, without providing any evidence, of wiretapping his phones in Trump Tower in the weeks before the November election.
"Reports concerning potentially politically motivated investigations immediately ahead of the 2016 election are very troubling," Spicer said in the statement, which he also posted on Twitter. "President Donald J. Trump is requesting that as part of their investigation into Russian activity, the congressional intelligence committees exercise their oversight authority to determine whether executive branch investigative powers were abused in 2016."
"Neither the White House nor the President will comment further until such oversight is conducted," Spicer added. He did not provide any further details on the President's request to Congress.
While Spicer said "reports" prompted the request, the White House still has not provided any evidence to back up the President's accusations. There are no credible reports to support Trump's claim that Obama ordered Trump's phones be monitored.
Instead, multiple former senior US officials have dismissed Trump's allegations, calling them "nonsense" and "false." Through a spokesman, Obama also rejected the claim that he ordered the tapping of Trump's phones.
House Intelligence Committee Chairman Devin Nunes said Sunday that his panel will look into Trump's allegations.
"One of the focus points of the House Intelligence Committee's investigation is the U.S. government's response to actions taken by Russian intelligence agents during the presidential campaign," the California Republican said in a statement. "As such, the committee will make inquiries into whether the government was conducting surveillance activities on any political party's campaign officials or surrogates, and we will continue to investigate this issue if the evidence warrants it."
Senate Intelligence Committee Chairman Richard Burr, of North Carolina, and Senate Majority Leader Mitch McConnell, of Kentucky, would not comment on Trump's call for an investigation into his allegations that the Obama administration monitored his phones.