James Clapper, the U.S. director of national intelligence, submitted his resignation Wednesday.

NBC News reported that Clapper, who began serving in his role in 2010, was looking forward to the end of President Barack Obama's second term because he planned to end his intelligence career at that time.

Clapper made good on that. According to CNN, he will retire at the end of Obama's term on Jan. 20.

"He signed his letter as required by all appointed administration officials but is finishing out his term," a spokesman from Clapper's office told the network.

It's unclear who Trump will select to lead the nation's intelligence efforts.

Clapper exits his post at a tumultuous time for the country, he said.

"Our nation is facing the most diverse array of threats that I've seen," Clapper said Thursday, according to CNN. "I will leave this job concerned about the impact of so-called lone wolves and home grown violent extremism. That is a very complex problem."

The 75-year-old Clapper is the fourth person to work as the director of national intelligence. Before he took office under President Barack Obama, he was the under secretary of defense for intelligence from 2007-2010. He also served as the director of the National Geospatial Intelligence Agency (2001-2006) and the director of the Defense intelligence Agency (1991-1995).

Clapper served in the military for 32 years and worked in some intelligence roles during and after the Vietnam War. Clapper retired in 1995 as a lieutenant general in the Army.

Clapper recently spoke about the cyber attack on a U.S.-based hosting firm that shut down several websites on the internet, saying he believes a "non-state actor" was behind it.

Last month, Clapper said Russia's alleged hacking into U.S. computer networks and the supposed interference it inserted into the presidential election was a "new aggressive spin on the political cycle."