US Secretary of State John Kerry stressed the need to move now to end the conflicts in Syria and Yemen in talks with top Saudi officials on Friday, a senior US official said.
Kerry also sought to reassure officials of the importance of US-Saudi ties a day after President Barack Obama was quoted in a US magazine as saying regional rivals Saudi Arabia and Iran need to "share the neighborhood" and establish a "cold peace."
Meeting at a Saudi military base outside Hafr al-Batin near the Saudi border with Iraq, Kerry held talks with Saudi King Salman, Crown Prince Mohammed Bin Nayef, Defense Minister Mohammed bin Salman and Foreign Minister Adel al-Jubeir.
"We have to talk about Syria," Kerry said after he met the king as he began a separate discussion with the three other officials, according to a US pool reporter accompanying him.
Syrian peace talks are set to get under way in Geneva next week, and the main Syrian opposition group, which is backed by Saudi Arabia, has said it will attend.
The UN-brokered talks will take place two weeks after the start of a cessation of hostilities agreement that has reduced the violence but not completely stopped the fighting, with further outbreaks reported in western Syria on Friday.
The cessation is the first truce of its kind in a five-year-old war that has killed more than 250,000 people and driven millions of Syrians from their homes.
"Kerry emphasized that now is the time to keep moving forward toward ending the conflicts in Syria and Yemen," a senior US State Department official said in an email.
Washington and allies including Saudi Arabia and Turkey back opposition groups representing political and armed factions in Syria's civil war while Russia and Iran support President Bashar al-Assad.
In another regional conflict, Riyadh and a coalition of Arab states entered Yemen's civil war a year ago in an attempt to restore President Abd-Rabbu Mansour Hadi after the Houthis and forces loyal to former president Ali Abdullah Saleh ousted him.
The US official said Washington supported UN efforts to get all the Yemeni parties into talks. He also said that during his meetings, "Kerry reaffirmed the strong US commitment to our valued and important partnership with Saudi Arabia."
Sunni-majority Saudi Arabia and Shi'ite majority Iran are locked in a regional power struggle. Saudi Arabia, a US partner, may have been irked by an article in The Atlantic magazine quoting Obama as saying the two "need to find an effective way to share the neighborhood and institute some sort of cold peace."