Spain's government Friday approved controversial new fines for holding unauthorised demonstrations, sparking protests from civil rights groups.

Following warnings from judicial authorities, Madrid watered down measures from an earlier bill, but maintained tough penalties for unauthorised demos if they are deemed a security threat.

Critics have branded the reform repressive. But Interior Minister Jorge Fernandez Diaz insisted it would "guarantee greater security for citizens with greater legal security... and protect the rights and freedoms of citizens".