The six-member Gulf Cooperation Council, of which Saudi Arabia is the most powerful member, expressed “profound worry,” the bloc’s secretary general, Abdullatif al-Zayani, said in a statement.
He said the law “contravenes the foundations and principles of relations between states, notably sovereign immunity.”
The Senate already approved the bill four months ago and it now goes before President Barack Obama.
The White House has signaled that he is likely to veto the bill but his veto can be overridden by a two-thirds majority of both houses.
Zayani expressed hope that the US administration “will not endorse this law… which will create a grave precedent.”
The draft law would allow attack survivors and relatives of terrorism victims to pursue cases in US federal court against foreign governments and demand compensation if such governments are proven to bear some responsibility for attacks on US soil.