James Woolsey, who headed the CIA under former President Bill Clinton, will serve as a senior adviser to Donald Trump on national security, defense, and intelligence, the Republican nominee’s campaign announced on Monday.

Woolsey, a self-described life-long Democrat, told CNN soon after the announcement that he supports Trump’s defense budget proposal, which includes a commitment to lift the restraints on defense spending, the Hill reported.

He also said that Trump is "more willing" to protect the privacy of classified information, citing Hillary Clinton’s use of a private email server during her time as secretary of state.

"She demonstrated a complete lack of understanding and an inability to lead the agency she headed in such a way as to maintain its mission and security," Woolsey said in a statement.

"Based on the emails thus far released we know that Secretary Clinton also lacks the ability to lead her senior managers while complying with and maintaining the basic protocols designed to protect our government’s sensitive and classified information. Mr. Trump understands the magnitude of the threats we face and is holding his cards close to the vest," he continued.

Woolsey served as director of the CIA from 1993 to 1995, though he never once met with former President Clinton one-on-one during his two-year tenure, according to Politico.

Woolsey was a strong supporter of invading Iraq in the wake of the Sept. 11, 2001 attacks, and heavily supported the U.S.’s 2003 intervention. Donald Trump has been a vocal critic of the Iraq War on the campaign trail.