Barack Obama has arrived in Jordan for talks with King Abdullah II - which are expected to focus on the Syrian war and the influx of refugees into the country.
It is the final stop on a four-day trip to the Middle East, which included his first visit as president to Israel and the Palestinian territories.
More than 400,000 Syrian refugees have crossed into Jordan to escape two years of bloodshed at home, crowding refugee camps and overwhelming aid agencies run by this important US ally.
Mr Abdullah has voiced fears that extremists and terrorists could create a regional base in his country.
Mr Obama will also seek to bolster Jordan's efforts to reform its government in an attempt to stave off an Arab Spring-style revolution that has led to the downfall of longtime leaders in Egypt, Tunisia and Libya.
After Air Force One touched down in the capital of Amman, Mr Obama headed by motorcade to al-Hummar Palace for meetings with the king.
"I apologise for the delay. We ended up having a dust storm," Mr Obama told Mr Abdullah after he was an hour late.
On Saturday, Mr Obama plans several hours of sightseeing, a tour of the fabled ancient city of Petra before the return trip to the White House.
In Israel, Mr Obama paid respects to the nation's heroes and to victims of the Holocaust. He also solemnly reaffirmed the Jewish state's right to exist.
He also toured the Yad Vashem Holocaust memorial, declaring afterward that the memorial illustrates the depravity to which man can sink but also serves as a reminder of the "righteous among the nations who refused to be bystanders".
Mr Obama was criticised in Israel for his 2009 Cairo speech in which he gave only the example of the Holocaust as reason for justifying Israel's existence.
In clear response to the criticism, at Yad Vashem, he said: "Here on your ancient land, let it be said for all the world to hear. The state of Israel does not exist because of the Holocaust, but with the survival of a strong Jewish state of Israel, such a holocaust will never happen again."
Accompanied by Israeli Prime Minister Benjamin Netanyahu and President Shimon Peres, Mr Obama laid wreaths at the graves of Theodor Herzl, the founder of modern Zionism and former Israeli Prime Minister Yitzhak Rabin, who was assassinated in 1995.