A top GOP national security icon just announced he’s backing Clinton over Trump

A high-ranking Republican has vowed to vote for Democratic candidate Hillary Clinton instead of his own party's Donald Trump, citing concerns over Trump's lack of interest in foreign policy issues, Politico reports.

Richard Armitage, who served as deputy secretary of state under George W. Bush, has vowed to vote for Clinton in what Politico calls "one of the most dramatic signs yet that Republican national security elites are rejecting their party’s presumptive nominee."

“If Donald Trump is the nominee, I would vote for Hillary Clinton,” Armitage told Politico. “He doesn't appear to be to be a Republican, he doesn't appear to want to learn about issues. So I’m going to vote for Mrs. Clinton.”

Armitage told Politico that many of his conservative friends with backgrounds in national security are confused about what to do.

Politico spoke to others off-the-record who have registered alarm over Trump's candidacy and are mulling whether to come out publicly and say so.

Last month, members of the intelligence community told National Public Radio they are uncomfortable with the prospect of providing Trump with national security briefings.

"He's never held public office before," CIA analyst Aki Peritz told NPR. "He's a business developer and a reality TV star. So if the United States starts giving Donald Trump classified briefings, it could be a disaster."

Peritz called Trump a "man famously with no filter."

Director of National Intelligence James Clapper told reporters that the process is set up " to ensure that everybody gets the same information and that we do comply with the need to protect sources and methods and comply with security rules."

Clinton has also come under scrutiny for handling of secure information after it came to light she used a private email server while serving as Secretary of State. Armitage in 2006 admitted he revealed the identity of CIA agent Valerie Plame after her husband, Joe Wilson, challenged the Bush administration over claims of weapons of mass destruction in Iraq.