The White House says President Donald Trump and Saudi King Salman bin Abd al-Aziz Al Saud have agreed to back safe zones in Syria and Yemen.
The two spoke by telephone Sunday, reaffirming the longstanding relationship between the United States and Saudi Arabia.
A White House statement said Trump asked for the king's support for safe zones, and that the king agreed.
They also said they will support what the White House called "other ideas" to help refugees driven from their homes because of war, and the "importance of rigorously enforcing" the nuclear deal with Iran, which Trump has fiercely criticized as a bad deal.
Trump spent the last two days reaching out by telephone to a number of world leaders. He also was to talk Sunday with the crown prince of the United Arab Emirates, Mohammed bin Zayed, and acting South Korean President Hwang Kyo-Ahn.
He spoke Saturday to Japan's Prime Minister Shinzo Abe, German Chancellor Angela Merkel, French President Francois Hollande and Australian Prime Minister Malcolm Turnbull.
In a much anticipated call, Trump also spoke with Russian President Vladimir Putin, agreeing to cooperate in defeating Islamic State and work for peace in Syria and throughout the world.
The White House said the hour-long call was "positive," and that it was "a significant start to improving the relationship" between Washington and Moscow, which has been badly strained in recent months, primarily over allegations that Russia interfered in the November presidential election.
Neither side mentioned U.S.-imposed sanctions on Russia, or the possibility they could be eased.
A Kremlin statement said Putin and Trump "thoroughly discussed" international issues, "including the fight against terrorism, the situation in the Middle East, the Arab-Israeli conflict, the sphere of strategic stability and nonproliferation, the situation around the Iranian nuclear program and the Korean Peninsula."
The talks also "touched upon ... the main aspects of the crisis in Ukraine," Moscow's statement said, adding: "It was agreed to establish a partnership on all these and other areas."