James Clapper, the US intelligence chief, resigns
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.
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.
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).
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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.
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.