Retired Lt. Gen. Michael Flynn on Friday accepted President-elect Donald Trump's offer to be his national security adviser, Fox News confirmed.

Flynn, who served as the director of the Defense Intelligence Agency (DIA) between 2012 and 2014, has advised Trump on national security issues for months. As national security adviser, he would work in the White House and have frequent access to the president.

The position does not require confirmation by the Senate. Whoever holds it is typically shielded from congressional requests to testify or produce documents.

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After leaving the DIA, Flynn became a virulent critic of the Obama administration and the Pentagon. He took issue with a wide range of national security policies, including the administration's approach to fighting ISIS and, more generally, its handling of global affairs.

Flynn asserted that he had been forced out of the DIA because he disagreed with the administration's approach to combating extremism. His critics, however, claimed he had mismanaged the agency and that his efforts to force change had met with internal resistance.



In recent public comments, including his fiery address at July's Republican National Convention, Flynn has emphasized his view that the threat posed by ISIS requires a more aggressive U.S. military, as well as his belief that Washington should work more closely with Moscow.

Flynn is also a champion of renegotiating the Iran nuclear deal, another foreign policy theme Trump pushed during the campaign.

But Flynn's warmth toward Russia has worried some national security experts. Flynn traveled last year to Moscow, where he joined Russian President Vladimir Putin and other Russian officials in a celebration of the RT network, Russia's government-controlled television channel. Flynn later explained that he had been paid for taking part in the event, but brushed aside concerns that he was aiding a Russian propaganda effort.



Flynn has also been outspoken in his alarms about the dangers of Islamist groups, complaining on CNN in June that the U.S. needs to "discredit" radical Islam, but that "we're not allowed to do that right now." He blamed the Obama administration in a New York Post op-ed in July for failing to design a coherent strategy for opposing ISIS. And in August, he spoke at an event in Dallas for the anti-Islamist group Act for America, saying that Islam "is a political ideology" and that it "definitely hides behind being a religion."



Flynn's dark warnings about Islam have not extended to the Islamist-leaning authoritarian Turkish government headed by President Recep Tayyip Erdogan. In an op-ed for the Washington newspaper The Hill just before the election, Flynn wrote that "our ally Turkey" needs support and echoed Erdogan's warnings that a "shady" Turkish leader now exiled in Pennsylvania should not be given safe harbor in the U.S. Erdogan has called for the extradition of the exile, Fethullah Gullen, but the Obama administration has made no move to comply.



Flynn's military experience might have made him seem like a natural choice to lead the Pentagon. But without a waiver from Congress, he is not eligible to be secretary of defense because federal law says "a person may not be appointed as secretary of defense within seven years after relief from active duty as a commissioned officer."

Two sources told Fox News earlier this week that Flynn's potential appointment is seen by Trump's team as a way to tap into his national security expertise, without subjecting him to intensive questioning.

During the campaign, Flynn was thought of as a potential running mate for Trump. However, he appeared to fall out of favor after implying that he was pro-choice in a television interview.

FLYNN CLARIFIES HIS ABORTION STANCE, SAYS HE'S 'PRO-LIFE'

Flynn told ABC's "This Week" in July that women "have to make the decision [on abortion] because they are the ones that are going to decide to bring up that child or not." The day after the interview aired, he told Fox News that he was a "pro-life Democrat."

With his public and fervent support for Trump, highlighted by his July convention appearance, Flynn challenged the military's apolitical traditions. He was not alone in that role. John Allen, a retired Marine general, spoke at the Democratic National Convention as a Hillary Clinton supporter. Their former colleague, retired Gen. Martin Dempsey, wrote in The Washington Post that Flynn and Allen were wrong to have participated as they did.



"The military is not a political prize," Dempsey wrote. "The American people should not wonder where their military leaders draw the line between military advice and political preference."



Flynn would not be the first retired general to be asked to serve as part of a president's national security team. Obama appointed retired Army Gen. David Petraeus as CIA director in 2011.



Colin Powell, who had served as chairman of Joint Chiefs of Staff at the pinnacle of his Army career, became secretary of state during President George W. Bush's first term. He also served as national security adviser to President Ronald Reagan from 1987 to 1989 while retaining his Army commission as a lieutenant general.



Retired Marine Gen. James Jones, a former commander of U.S. and NATO forces in Europe, served as Obama's first national security adviser.



Fox News' Ed Henry and James Rosen and the Associated Press contributed to this report.