Saudi Arabia has criticized a US bill that would allow families of victims of the September 11, 2001, attacks in New York to sue the Gulf country, Saudi state media reported on Friday.
US Congress voted overwhelmingly on Wednesday to override a veto by President Barack Obama on the Justice Against Sponsors of Terrorism Act (JASTA).
The Saudi Foreign Ministry said the bill was a "source of big concern."
"Weakening sovereign immunity will have a negative impact on all nations, including the United States," the ministry said in a statement, according to the official Saudi news agency SPA.
Saudi newspapers also lashed out at JASTA.
"No doubt the economic response will include the possible sale of Saudi assets in the United States," the pro-government newspaper Okaz said in an editorial.
Al Jazirah, another Saudi newspaper, called JASTA "glaring American blackmail."
Saudi Arabia, a key regional US ally, had earlier threatened to freeze US securities and other assets worth 750 billion dollars if JASTA were applied.
The measure would narrow the sovereign immunity of other governments in US federal courts, allowing lawsuits against foreign states inside the US as a result of a tort, including an act of terrorism, committed anywhere by a foreign state or official.
Relatives of the victims of the 2001 attacks, in which hijackers crashed planes in New York, Washington DC and Pennsylvania, have long sought to sue Saudi Arabia, claiming links between the kingdom and al-Qaeda, the terrorist network that carried out the attack.
Fifteen of the 19 hijackers on September 11, 2001, were Saudi nationals.