Director of National Intelligence James R. Clapper Jr. said Thursday that he has submitted his letter of resignation to President Barack Obama, cementing his long-declared plan to leave his job as the nation's spy chief when a new president is sworn in. 
 
 "I submitted my letter of resignation last night, which felt pretty good," Clapper said in testimony Thursday morning before the House Intelligence Committee. "I have 64 days left and I would have a hard time with my wife for anything past that." 
 
 U.S. officials emphasized that Clapper's resignation was unrelated to the election victory of Donald Trump, who has publicly dismissed the work of U.S. spy agencies on critical issues, including Russia's interference in the election and Moscow's involvement in the war in Syria. 
 
 Clapper began his career as a rifleman in the U.S. Marine Corps Reserve and went on to serve in a series of intelligence-related assignments over the past 50 years, culminating in his appointment as director of national intelligence in 2010. 
 
 The disclosure that Clapper has submitted his letter comes at a time of widespread apprehension among U.S. intelligence agencies over how they will be treated in a Trump administration. One of the leading candidates to serve as CIA director, former House Intelligence Committee Chairman Mike Rogers, was expelled from the Trump transition team this week as part of an internal purge. 
 
 Clapper has only hinted at his views of Trump, saying at a security conference in July that the divisive rhetoric of the presidential campaign had worried foreign allies. Asked how he responded to such concerns, Clapper said, "I tell them that I appreciate them sharing their concerns, that it is our process in the United States and hopefully it will all come out right." 
 
 U.S. intelligence agencies have repeatedly been at odds with Trump. Clapper's office released a statement in October that Russia was directly involved in a cyber campaign designed to disrupt the U.S. election, and that the operation was almost certainly approved by Russian President Vladimir Putin. 
 
 Trump has rejected those conclusions, saying during one of the presidential debates that it was just as likely that the election hacks were orchestrated by "somebody sitting on their bed that weighs 400 pounds." 

 Image copyright Getty Images Image caption Mr Clapper served in the Obama administration for six years 
 
 US Director of National Intelligence James Clapper has submitted his letter of resignation, he has told a congressional panel. 
 
 He told the House Intelligence Committee that "it felt pretty good". 
 
 The 75-year-old top American spy had been expected to step aside, as President-elect Donald Trump prepares to appoint his own officials. 
 
 Analysts believe that he is sending a signal to the Trump administration that they must now speed up the transition. 
 
 Mr Trump has denied that his transition team is in turmoil, despite having only filled two postings so far. 
 
 One of his close advisers, Kellyanne Conway, told reporters at Trump Tower in New York that announcements would be made before or after Thanksgiving, which is one week away. 
 
 Mr Clapper will remain in post until President Barack Obama leaves office. 
 
 "I submitted my letter of resignation last night which felt pretty good. I've got 64 days left," he said. 
 
 Image copyright Getty Images 
 
 Analysis by Tara McKelvey, White House reporter 
 
 At cocktail parties James Clapper liked to hold forth - about the ineptitude of North Korean nuclear scientists among other things. Yet he's best known for misleading the US senate about mass data collection (he claimed the NSA didn't gather huge amounts of data). 
 
 A more discreet man would've waited till President-elect Trump chose all his cabinet members to announce his resignation. But Clapper is outspoken (and a snappy dresser, wearing a hand-tied bowtie - "like James Bond", said an ex-CIA analyst - at a recent party), and subtlety was not his style. 
 
 Overall, he was a flawed spymaster, but one whom many in Washington now say they'll miss. Describing his job as "a nearly impossible one", a secrecy expert, Steven Aftergood, told me: "I don't envy his successor." 
 
 Committee members jokingly asked him to stay for four more years. 
 
 A spokesperson for the Office of the Director of National Intelligence told the BBC that "as required of all appointed Administration officials, DNI Clapper has signed a letter of resignation effective at noon on January 20, 2017." 
 
 Mr Clapper has authority over 17 different agencies including the Central Intelligence Agency (CIA), the Drug Enforcement Administration (DEA), and the (Federal Bureau of Investigation (FBI). 
 
 More than 107,000 employees report to him with a combined budget of over $52 billion (£41.8 billion). 
 
 In a profile published by Wired magazine only hours before his announcement, he said that he never questioned the morality of his profession. 
 
 In his role, he has often been in the position of defending the National Security Agency (NSA), just one of the covert agencies that his office oversees. 
 
 Its image was badly damaged after Edward Snowden revealed how they collect information on American citizens. 
 
 Image copyright Getty Images Image caption Snowden's leaks put the NSA - and Clapper - under scrutiny 
 
 During a 2013 congressional hearing, Mr Clapper was asked: "Does the NSA collect any type of data at all on millions, or hundreds of millions, of Americans?" 
 
 "No, sir," Mr Clapper replied. 
 
 "It does not?" the incredulous senator responded. 
 
 "Not wittingly," Clapper said. "There are cases where they could inadvertently, perhaps, collect, but not wittingly." 
 
 On Thursday, he was asked if Mr Trump will open up a rapprochement with Russia's President Vladimir Putin, but answered that he does not predict a "significant change in Russian behaviour". 
 
 Mr Clapper has served in the job for six years after previously working for the US Air Force and the Defence Intelligence Agency.
– US Director of National Intelligence James Clapper has tendered his resignation, NBC News reports. The 75-year-old Clapper has been planning to step down for a while, and he said finally handing in his letter "felt pretty good." The BBC reports the intelligence chief told House officials that "I've got 64 days left," indicating that he would stay on until Donald Trump's inauguration. Clapper oversees 17 different federal agencies, including the CIA, NSA, FBI, and DEA; he got the job in August 2010, the Chicago Tribune notes, and has had a contentious tenure that was largely defined by the high-profile drama surrounding Edward Snowden and the revelation of large-scale NSA surveillance programs