The United States remains committed to its Gulf Arab partners, US Secretary of State Antony Blinken told Gulf diplomats in Saudi Arabia on Wednesday, at a time of rapidly shifting regional alliances, AFP reported.

Blinken spoke during a Gulf Cooperation Council ministerial meeting in the capital Riyadh following talks with Saudi Foreign Minister Prince Faisal bin Farhan and the kingdom's de-facto ruler, Crown Prince Mohammed bin Salman.

"The United States is in this region to say we remain deeply invested in partnering with all of you," Blinken said at the opening of the US-GCC ministerial meeting on strategic partnership.

"The GCC is the core of our vision for a Middle East that is more stable, more secure, more prosperous," he added.

The meetings came a day after Blinken flew into Jeddah, kickstarting a visit aimed at boosting ties with ally Saudi Arabia, which has begun forging closer relations with Washington's rivals.

The three-day visit is Blinken's first since the kingdom restored diplomatic ties with Iran.

On Tuesday, the day Blinken arrived, Iran reopened its embassy in Riyadh after a seven-year closure, with Iranian Deputy Foreign Minister Alireza Bigdeli hailing a "new era" in ties.

On the same day, Prince Mohammed hosted Venezuelan President Nicolas Maduro, the head of a fellow oil power who has long sparred with Washington.