Former US Secretaries of State Colin Powell (L) and Hillary Clinton speak during a ceremony to break ground on the US Diplomacy Center at the US State Department in Washington, DC, September 3, 2014.
Jim Watson | AFP | Getty Images
Colin Powell said he will vote for Hillary Clinton at a luncheon on Tuesday.
NBC News confirmed with Powell that he is endorsing and voting for the Democratic nominee.
Powell, a retired four-star general, served as chairman of the joint chiefs of staff under both George H.W. Bush and Bill Clinton. He also served as George W. Bush's secretary of state.
In 2008, Powell announced his endorsement of Barack Obama on NBC's "Meet the Press."
— NBC News' Andrea Mitchell contributed to this report.