RIYADH: Saudi Arabia has warned of “disastrous consequences” from a United States (US) law allowing 9/11 victims to sue the kingdom, in a major spike in tension between the longstanding allies.

The warning came after the US Congress voted overwhelmingly on Wednesday to override US President Barack Obama's veto of the Justice Against Sponsors of Terrorism Act (JASTA).

JASTA allows attack survivors and relatives of terrorism victims to pursue cases against foreign governments in US federal court and to demand compensation if such governments are proven to bear some responsibility for attacks on US soil.

A Saudi foreign ministry source late on Thursday called on the US Congress “to take the necessary measures to counter the disastrous and dangerous consequences” of the law.

The unnamed spokesman, cited by the official Saudi Press Agency, said the law is “a source of great worry.”

This law “weakens the immunity of states”, and will have a negative impact on all countries “including the United States,” the spokesman said, expressing hope that “wisdom will prevail.”

In opposing the law, Obama said it would harm US interests by undermining the principle of sovereign immunity, opening up the US to private lawsuits over its military missions abroad.

The erosion of sovereign immunity is also a concern among the six-nation Gulf Cooperation Council, of which Saudi Arabia is the most powerful member.

Saudi Arabia's Gulf allies have lined up beside Riyadh to criticise the legislation.

Late on Thursday, United Arab Emirates foreign minister Anwar Gargash described the move as “a dangerous precedent in international law that undermines the principle of sovereign immunity and the future of sovereign investments” in the US.

“The populism surrounding the JASTA law overcame the rationality required in matters of international law and investments,” he tweeted, warning of its “long term and dangerous implications.”

Decades-old ties

A senior Saudi prince reportedly threatened to pull out billions of dollars of US assets if JASTA became law, though Saudi officials have distanced themselves from such threats.

Gargash criticised what he said was “illogical and demagogic” incitement in the US against Saudi Arabia which has “suffered most from extremism and terrorism.”

However, he said reactions should “not be hasty. Easing damage requires focused and joint action.”

The UAE, a US ally in the Gulf, has played a major role alongside Saudi Arabia in its war against Iran-backed rebels in Yemen.

Bahrain, another GCC ally of Riyadh, has also criticised the bill, which it warned will harm the US.

A Saudi newspaper on Friday sent a message to US lawmakers through a headline that played with the letters of “JASTA”.

They “Just Acted Stupidly Toward Allies,” the Arab News said on its front page.

Analysts have warned that Saudi Arabia could reduce valuable security and intelligence cooperation with ally Washington after the Congressional vote.

Riyadh and Washington have a decades-old relationship based on the exchange of American security for Saudi oil.

Yet Saudi Arabia was home to 15 of the 19 Al Qaeda hijackers who carried out the September 11, 2001 attacks on the United States which killed nearly 3,000 people.

Riyadh denies any ties to the plotters.

Ties between Riyadh and Washington became increasingly frayed under Obama, but analysts said security cooperation and intelligence sharing remained solid.