Saudi Arabia says it is satisfied with assurances from Washington over the Iran nuclear deal following President Obama’s meeting with King Salman.
Iran and Yemen topped the agenda as the king visited America for the first time since coming to the throne in January.
Riyadh was seeking support, fearing that its rival Tehran poses a threat to the Gulf region following the agreement struck in July.
There are Gulf Arab fears that a lifting of sanctions will enable the Islamic Republic to pursue destabilising policies in the Middle East.
The Saudis also wanted to shore up Saudi-US relations after a period of tension as the two leaders held talks at the White House.
They have been worried about what they see as a US withdrawal from the Gulf region, a lack of direct action against the Assad government in Syria, and a perceived tilt towards Iran since the Arab spring uprisings.
The Saudi Foreign Minister Adel al-Jubeir emerged heartened from the meeting to speak to reporters.
“The Kingdom of Saudi Arabia was satisfied with these assurances after having spent the last two months consulting with our allies in Europe and other places with regards to this agreement. And, we believe that this agreement will contribute to security and stability in the region by preventing Iran from acquiring a nuclear capability, and we hope that the Iranians will avail themselves of this opportunity in order to use the openness to the world and the additional income that they receive to fund domestic development rather than engage in nefarious activities in the region,” he said.
Outside the White House there was a protest against the Saudi king’s presence, amid anger over policy in Yemen.
A coalition of Gulf states led by Riyadh and backed by Washington has been targeting Houthi forces allied to Tehran.
But the mounting civilian death toll has brought international criticism.
Demonstrators waved Yemeni flags and carried banners with slogans such as “End the blockade in Yemen” and “Stop killing Yemeni civilians”.