Former Vice President Dick Cheney criticized President Donald Trump's foreign policy, even comparing it with that of former President Barack Obama, in a striking rebuke of the president by a member of his own party.

Speaking with Vice President Mike Pence this weekend at a closed-door retreat hosted by the American Enterprise Institute in Sea Island, Georgia, Cheney warned that American allies were questioning the dependability of the U.S. as a result of the Trump's public statements. Cheney, known for his hawkish foreign policy views, specifically highlighted Trump's public complaints about the role of NATO and the surprise announcement of the withdrawal of troops from Syria.

Cheney's remarks, which were first reported Monday by The Washington Post, were confirmed by a person in the room. The person requested anonymity because of the conference's off-the-record nature.

Cheney also raised alarm over news reports that Trump does not spend sufficient time with his intelligence briefers as well as over frequent staff churn in key national security postings. Cheney also suggested repeatedly that Trump's transactional view of foreign policy — including a focus on what allies contribute to their defense — was misguided.

Pence joked about the absence of "softball" questions before the annual gathering of conservative thinkers, politicians and business leaders. He also sought to counter some of Cheney's criticisms about Trump's handling of North Korea and Syria. A spokesperson for Pence confirmed the account but declined to discuss the exchange.

Since leaving office, Cheney has largely avoided the public spotlight. While his remarks were delivered in private, they reveal how deeply some GOP stalwarts oppose many of Trump's foreign policy moves. The president's brash "America First" pronouncements have been met with concern and condemnation from many traditional Republicans.

Earlier this year, congressional Republicans joined with Democrats to express disapproval of Trump's planned moves to withdraw U.S. troops from Syria and Afghanistan.