TBILISI, Georgia (AP) — A non-governmental organization in Georgia said Thursday it is preparing a lawsuit in the country's constitutional court to challenge a law that critics say will stifle news media and independent organizations.

The law will require media and non-governmental organizations that receive more than 20% of their funding from abroad to register as representing the interests of foreign powers. Opponents claim that the law would discredit such organizations and that it will obstruct Georgia's bid to join the European Union.

Massive demonstrations have filled the streets of the Georgian capital Tbilisi for weeks to protest the measure, whose foes call it “the Russian law” because of similar laws in Russia pushed by the Kremlin.

President Salome Zourabichvili vetoed the law after it was passed by parliament this month, but the parliament overrode the veto on Tuesday. The law now must be accepted by Zourabichvili by Sunday, or the speaker of the parliament can accept it if she does not.

Georgia's Civil Society Foundation said in a statement that, “We declare that we will not live by the Russian law and will use all domestic and international mechanisms to prevent its action until the law is unconditionally repealed. To this end, we are preparing a lawsuit to be filed with the Constitutional Court of Georgia and will consider it in the near future."

Anri Okhanashvili, chairman of the judicial committee of the parliament, dismissed the initiative.

“We are ready anywhere, be it the Constitutional Court or other institutions, to defend this legislative act that is adopted in favor of the interests of our country," he said.