President Donald Trump arrived in Saudi Arabia Tuesday morning to meet with the country's leaders about Iran's nuclear program, oil prices, and the war in Gaza, as well as investments.The Saudi Crown Prince greeted Trump on the tarmac ahead of a state visit and dinner. Trump will speak at an investment conference. He's expected to announce new arms deals with Saudi Arabia, highlighting the U.S.' relationship with Middle Eastern countries.At the top of mind for the Gulf nations during the visit is the war in Gaza, which Trump wants to end. He also plans on touting Hamas' recent release of the last American hostage as a "goodwill gesture" toward a peace deal, although Israel says it is ramping up plans to occupy Gaza.Trump mentioned he may support lifting sanctions on Syria as the country transitions to a new government and will likely update leaders on talks to contain Iran's nuclear program. He has also floated the idea of going to Turkey if a sit-down between the leaders of Ukraine and Russia happens, discussing a possible ceasefire in the ongoing war.Trump's four-day, three-nation visit will include stops at the United Arab Emirates and Qatar. He is considering accepting a $400 million Air Force One replacement from Qatar's ruling family, a gift that has raised ethical, legal, and security concerns in the U.S."I would never be one to turn down that kind of an offer. I mean, I could be a stupid person and say, 'No, we don't want a free, very expensive airplane,'" Trump told reporters Monday.The U.S. Constitution requires congressional approval for federal officials to accept foreign gifts, a matter Trump will likely face more questions about during his Middle East trip."Free is good. We don't have a lot of money right now to buy things like that," Sen. Tommy Tuberville, R-Alabama, said. "If it's legal for him to accept that gift and be able to fly on that for the next four years or 3 1/2 years, I think it's great. It'll save us money."Others, particularly Democrats, criticized the idea."This idea is just so outrageous and so obviously a conflict of interest for the president," Sen. Chris Van Hollen, D-Maryland, said. "This is grift, pure and simple."