US Secretary of State John Kerry reassured Saudi Arabia on Sunday of the "solid relationship" between both countries, even after the lifting of sanctions on Iran.

US Secretary of State John Kerry reassured Saudi Arabia on Sunday of the "solid relationship" between both countries, even after the lifting of sanctions on Iran.

"We have as solid a relationship, as clear an alliance, and as strong a friendship with the kingdom of Saudi Arabia as we've ever had," Kerry said before departing Riyadh for Laos at the end of a 24-hour visit.

"Nothing has changed because we worked to eliminate a nuclear weapon with a country in the region," he added. "We will continue to work in the region with our friends and our allies."

The historic deal with Tehran - backed by the United States and five other major powers - led this month to the lifting of crippling economic sanctions on Iran.