Transcript for Trump arrives in Riyadh, Saudi Arabia, for his first foreign trip as president

This is a high-stakes eight-day, five-country mission which the white house hopes might turn the page on the investigations and allegations raging here at home. Speaking of which overnight as the president crossed the atlantic we learned that the fired FBI chief James Comey will, in fact, testify before congress and do so publicly sometime after memorial day. Comey will almost certainly be asked about reports that he accused the president of asking him to shut down the investigation into former national security adviser Mike Flynn as well as his ties to the Russians. That announcement about Comey's testimony came just hours after "The New York Times" reported that the president discussed Comey's firing during an oval office meeting with the Russian foreign minister reportedly calling Comey a, quote, nut job. Also this morning sources tell ABC news the investigation into potential Russian collusion has, in fact, reached the white house and unnamed staffer close to the president is now under the microscope. We have team coverage this morning but we're going to begin with ABC's Cecilia Vega who is with the president in Saudi Arabia. Good morning to you, Cecilia. Reporter: Hey, Paula, good morning to you. This is an American first never before has a president set foot on Saudi soil for his first trip abroad but that cloud of chaos that you were just talking about is following president trump here even though the white house is trying for a reset. Air force one touching down in Saudi Arabia this morning. A red carpet welcome even if it took a while to lay out that carpet and roll out those stairs. ??? president trump receiving the royal treatment, the Saudi king right there to greet him and the first lady at the king's personal terminal used exclusively for the royal family and their guests. For president trump, first stop ceremonial coffee with the king, the microphones picking up their chatter. Do you spend a lot of time in New York? Reporter: Outside greeted with streets lined in america flags. Giant billboards showing him and the Saudi king. A warm welcome for president trump in the capital city of Riyadh. See all the flags on the streets. It's not just that political chaos, it's his comments from the campaign trail. From his thoughts on Islam. I think Islam hates us. There's something -- there's something there that there's a tremendous hatred. To that Muslim ban. Donald J. Trump is calling for a total and complete shutdown of muslims entering the United States. Reporter: His first foreign trip jam packed. Eight days, five countries with stops at the world's great religious centers from Saudi Arabia, the birthplace of Islam to Israel and then the Vatican. An ambitious agenda but the question this morning, how successful can president trump be abroad with a firestorm back home? And tomorrow the president is expected to deliver a big speech to the Muslim world calling on it to end extremism. It was written by Stephen Miller, Paula, the same aide who helped on that travel ban. And that speech is expected to preach religious tolerance. I have to ask you about that visual. First lady Melania is drawing attention for not wearing a head scarf. Yeah, and that is an example of the microscope the president and first lady are under under a trip like this but she is following in the footsteps of Michelle Obama who did not wear a head scarf during her visit hugely controversial back then seen as a sign of disrespect in this religiously conservative country. Among the people who criticized Michelle Obama back then, Donald Trump. Yes, Cecilia, thanks for your reporting. We know you'll be there for every step of the wayan 0 the trip. Here at home there's been no

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