WASHINGTON – Director of National Intelligence Dan Coats is stepping down soon after a tenure that featured clashes with President Donald Trump over Russia, North Korea, and other national security issues.

Trump confirmed the departure Sunday in a tweet. The president also announced he will replace Coats with Rep. John Ratcliffe, R-Texas. Trump said Coats will leave office on August 15.

“I would like to thank Dan for his great service to our Country,” Trump said.

Coats, in his resignation letter, touted accomplishments that included his appointment in July of a new czar within the intelligence community to oversee election-security efforts.

"The Intelligence Community is stronger than ever, and increasingly well prepared to meet new challenges and opportunities," Coats wrote. "As we have previously discussed, I believe it is time for me to move on to the next chapter of my life."

As for his new nominee to the post, Trump noted on Twitter that Ratcliffe is a former U.S. attorney who “will lead and inspire greatness for the Country he loves.”

The Senate must still confirm Ratcliffe as the new director of national intelligence.

Senate Minority Leader Chuck Schumer, D-N.Y., said it would be a "big mistake" for his GOP colleagues to "elevate such a partisan player to a position that requires intelligence expertise and non-partisanship."

"It’s clear that Rep. Ratcliffe was selected because he exhibited blind loyalty to President Trump with his demagogic questioning of former Special Counsel Robert Mueller," Schumer said of last week's House hearings.

Senate Majority Leader Mitch McConnell – who said he was sorry to see Coats go – said the intelligence community has to be able to deliver "unvarnished hard truths" to both the White House and Congress.

"Dan Coats was such a leader," McConnell, R-Ky., said.

The top Democrats on the House and Senate intelligence committees likewise praised Coats for not being afraid to stand up to Trump.

"He has had the independence and strength to speak truth to power," tweeted Rep. Adam Schiff, D-Calif.

Coats has clashed with Trump , and the former Indiana senator has widely been considered among the most vulnerable members of the president's administration – even as both men have downplayed talk of tension.

At a time when Trump was repeatedly describing the situation on the U.S.-Mexico border as a national security crisis, Coats declined to include immigration as a major threat facing the country when he spoke to lawmakers in January.

Coats also appeared to break with the White House on North Korea, asserting that Pyongyang was unlikely to give up its nuclear weapons program. Trump has made nuclear disarmament a condition of lifting U.S. sanctions on North Korea and has held up that goal as central to his effort to improve relations with North Korean leader Kim Jong Un.

Trump later asserted that his intelligence officials had been taken out of context.

Trump has previously considered Ratcliffe for other jobs in the administration.

During last week’s high profile hearing, Ratcliffe admonished former special counsel Robert Mueller for saying he could not exonerate Trump on obstruction of justice claims.

Ratcliffe told Mueller, “nowhere does it say that you were to conclusively determine Donald Trump's innocence or that the special counsel report should determine whether or not to exonerate him.”

While agreeing with Democrats that Trump “is not above the law,” Ratcliffe added: "But he damn sure should not be below the law.”

Coats had come under pressure in the job before, including for his remarks after the president's widely criticized press conference with Russian President Vladimir Putin last summer in Helsinki. Trump initially said he had no reason to doubt Putin's assertions Russia did not meddle in the 2016 election, despite U.S. intelligence agencies reaching that very conclusion more than a year before.

Coats, one of Trump’s most long-serving aides, appeared to grow increasingly critical of the president in the aftermath of the Helsinki summit, including with a statement following the meeting affirming Russia tried to influence the 2016 election. Trump had cast doubt on that conclusion – and on Coats – hours earlier.

As Coats was giving an interview to NBC last year, the White House announced Trump would invite Putin to Washington – a revelation that appeared to catch the nation’s spy chief off guard.

“Say that again?” Coats said.

“OK,” he added. “That is going to be special.”

Despite denials by Putin, Coats has steadfastly maintained the Kremlin-linked Internet Research Agency created social media accounts to sow division within the American electorate and that Russian hackers targeted businesses, state and local election divisions and Democratic party officials.

Coats said in a July 13 speech that the warning lights on interference were “blinking red."

Coats' exit sets up a showdown in the Senate, where Trump’s nominee to replace Coats will face mounting, bipartisan concern over the president’s approach to Russian, Iran and North Korea.

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Coats, a Republican who served in the Senate in the 1990s and was elected again in 2010, was appointed in March 2017, to serve as the director of national intelligence, succeeding James Clapper. Created in response to the 2001 terrorist attacks, the DNI is charged with coordinating the work of the nation’s intelligence agencies and briefing the president every day on the findings.

A former ambassador to Germany under President George W. Bush, Coats began his political career in Washington in the office of former Rep. Dan Quayle, R-Ind. He was elected to Quayle’s seat in the House in 1980 and was appointed to fill his Senate seat when Quayle became vice president nine years later.

In a White House that has sent conflicting signals on Russia, particularly about its role in the 2016 election, Coats was a reliable hawk on Moscow. He was among several lawmakers banned from traveling to Russia in 2014 after the U.S. slapped new sanctions on the country.

“While I’m disappointed that I won’t be able to go on vacation with my family in Siberia this summer,” Coats joked at the time, “I am honored to be on this list.”

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