The U.S. Supreme Court would hear an Obama administration appeal against moves by a human rights group in Los Angeles which seeks to legalize providing support to the LTTE and the Kurdistan Workers Party in Turkey.

The justices agreed to review a U.S. appeals court ruling that struck down as unconstitutionally vague a law that makes it a crime to provide support to a foreign terrorist group.

The challenge had been brought by groups and individuals who want to provide support to the LTTE in Sri Lanka and the Kurdistan Workers Party in Turkey. The State Department has designated both as foreign terrorist groups.

The law, first adopted in 1996, was strengthened by the USA Patriot Act supported by then-President George W. Bush and approved by Congress right after the Sept. 11 attacks in 2001. It was amended again in 2004.

Convictions under the law, which bars knowingly providing any service, training, expert advice or assistance to a designated foreign terrorist group, can result in sentences of 15 years to life in prison.

The law does not require any proof that the defendant intended to further any act of terrorism or violence by the foreign group.

The Obama administration appealed to the Supreme Court and called the law "a vital part of the nation's efforts to fight international terrorism."

Since 2001, the United States has charged about 120 defendants with material support of terrorism and about half have been convicted, the Justice Department said.