The sudden upheaval that shattered ties between Iran and Saudi Arabia over the weekend also saddled the Obama administration with unexpected complications in what already was a long-shot bid to ease the crises of the Middle East.
Administration officials voiced rising concern that the conflict between Iran and Saudi Arabia could undermine their broader regional efforts—in particular ending the Syrian civil war.
Secretary of State John Kerry had been pressing Tehran and Riyadh for months to establish a direct diplomatic channel to address the Syria conflict.
The two countries reluctantly agreed late in 2015 to join a multinational peace process. That led to a United Nations plan for a cease-fire and peace talks, but the latest developments raise questions about its viability.
The conflict is also exposing deteriorating relations between the U.S. and Saudi Arabia under President Barack Obama. Saudi officials have repeatedly pressed the White House to take more-aggressive steps to check what they say is Iran’s regionwide efforts to destabilize Arab countries.
Saudi officials have warned that the nuclear agreement reached in July between world powers and Iran would significantly strengthen Iran’s finances while only scaling back its nuclear capabilities for a few years.