"That's an internal Iranian matter", Saudi Foreign Minister Adel al-Jubeir told journalists when asked his expectations for Friday's presidential vote in Iran.
The Stars and Stripes are flying in Riyadh's streets, intermixed with Saudi flags.
"We are expecting to have nearly 37 leaders, kings and heads of state".
Trump has vowed to stimulate the U.S. economy by boosting manufacturing jobs. The White House is aware of reports that an American diplomat refused to allow Netanyahu to join Trump on the visit, but an official cautioned that the reported comments did not reflect the president's views.
Behind the scenes, the Trump administration and Saudi Arabia have been conducting extensive negotiations, led by White House senior adviser Jared Kushner and Saudi Deputy Crown Prince Mohammed bin Salman.
"Historic Summit. Brighter Future", declares an official website for Trump's visit, counting down the seconds until it all starts. They see great rule of law.
It is important for Trump to make clear to our Arab allies that the United States is back and fully engaged in the Middle East.More news: Fractious House panel at center of latest Trump probes
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English edition of Asharq Al-Awsat - the world's premier pan-Arab daily.
The United States has been the main supplier for most Saudi military needs, from F-15 fighter jets to command and control systems worth tens of billions of dollars in recent years.
Sunday will also see the USA president, along with Jordan's King Abdullah II, take part in a meeting of Twitter users who will discuss means of fighting extremism in the digital age.
The first stop is Saudi Arabia, followed by Israel and then to Europe, including to Brussels for a North Atlantic Treaty Organisation summit.
American country singer Toby Keith, known for songs such as "Whiskey Girl" and "Beer For My Horses", is scheduled to perform in the Saudi capital, Riyadh, this weekend in an event that coincides with President Donald Trump's first overseas visit.
Another area that is expected to be discussed at length, which is related to the arms deal, is the region's efforts to fight the threat of Islamic State of Iraq and Syria (Isis).
There are expected to be about 10 oil sector deals signed during the visit, between the state oil company Saudi Aramco and U.S. oil services companies including Schlumberger (which has one of its headquarters in the Houston area), Halliburton, McDermott International, Nabors Industries, Rowan Companies (also headquartered in Houston) and others, according to oil industry sources.