His four-day swing through Saudi Arabia, Qatar and the United Arab Emirates, which ends Friday, put a spotlight on Trump’s transactional approach to foreign affairs as he was feted by autocratic rulers with a trio of lavish state visits where there was heavy emphasis on economic and security partnerships.

There are two provisions in the U.S Constitution that place restrictions on the president receiving an emolument, or gift, from foreign governments or from federal or state governments. One provision states that Congress must approve any gift from a "King,