KHARTOUM (Reuters) - Sudan condemned on Tuesday a U.S. law that would allow families of victims of the Sept. 11, 2001 attacks to sue governments for damages, saying it undermined state sovereignty and could provoke reciprocal legislation.

Sudan hosted Osama bin Laden, the al Qaeda leader behind the attacks, from 1991-1996, although it has denied allegations that it funded him. Its government was among dozens of defendants named in a 2002 lawsuit filed by families of Sept. 11 victims.

The U.S. Senate and House of Representatives voted overwhelmingly last Wednesday to approve the Justice Against Sponsors of Terrorism (JASTA) legislation, which grants an exception to the legal principle of sovereign immunity in cases of terrorism on U.S. soil.

"This act clearly violates the sovereignty and immunity of states and could lead the world into legislative chaos," a statement from Sudan's presidency said.

"Sudan would not rule out several other countries drafting laws to lift sovereign immunity against countries that have laws which do not respect sovereign immunity, based on the principal of reciprocal treatment."

The legislation will allow the families of those killed in the 2001 attacks on the United States to seek damages from the Saudi government. Fifteen of the 19 hijackers were Saudi. Riyadh has denied longstanding suspicions that it backed the attackers.

Saudi Arabia said on Monday the law represented a threat to international relations. Sudan is an ally of Saudi Arabia.

(Reporting by Khalid Abdelaziz; Writing by Nadine Awadalla; Edited by Dominic Evans)