Analysts say Saudi Arabia could curb business and security ties with the US, after Congress on Wednesday passed a law allowing lawsuits against Riyadh over the September 11 attacks.
"I'm afraid that this bill will have dire strategic implications" for the United States, Salman al-Ansari, the president of the Saudi American Public Relation Affairs Committee (SAPRAC), told AFP.
"This partnership has helped provide US authorities with accurate intelligence information" that helped stopped attacks, said Ansari, whose committee is a private initiative to strengthen Saudi-US ties.
There was no official reaction from Saudi Arabia, and in the short-term, few expect little more reaction than a curt statement of disapproval from Riyadh.
Riyadh has always dismissed suspicions that it backed the attackers, who killed nearly 3,000 people under the banner of militant group Al Qaeda. Fifteen out of the 19 hijackers were Saudi nationals.
The Saudi Government financed an extensive lobbying campaign against the "Justice Against Sponsors of Terrorism Act," or JASTA, in the run-up to the vote, and warned it would undermine the principle of sovereign immunity.
But Saudi officials stopped short of threatening any retaliation if the law was passed. The long-standing alliance between the kingdom and the United States is one of the cornerstones of the Middle East's politics, security and trade, and in their reactions on Thursday some Saudis said JASTA would jeopardise what they see as an interdependent relationship.
"What would happen if Saudi Arabia froze its cooperation with the United States with regards to counter-terrorism as a response to JASTA?" Salman al-Dosary, editor-in-chief of the pan-Arab, Saudi-owned Al Sharq al-Awsat newspaper, wrote on Twitter.
Some analysts have speculated that Riyadh could retaliate by curbing US trade with the biggest Arab economy or restrict cooperation on security, a crucial relationship for US counter-terrorism and for peace efforts in Arab conflicts.
Political Theodore Karasik of Gulf State Analytics wrote on al Arabiya website that JASTA would "ignite a firestorm of legal warfare that will directly undermine political relationships at a time when robust ties to fight terrorism is required."
He said the measure could also disrupt sweeping economic reforms meant to boost the private sector and foreign investment and wean the kingdom off oil dependence.
The Saudi riyal fell against the US dollar in the forward foreign exchange market on Thursday after the bill was passed.
Some analysts speculated that bilateral trade and investment could be hurt. The kingdom owns $96.5 billion of US Treasury bonds, and is believed to hold at least that sum in other US assets and bank accounts.