Edward Snowden, who exposed the existence of highly invasive U.S. surveillance programs in 2013, warned this week that Japan might be moving closer to achieving sweeping surveillance of ordinary citizens with a bill that gives the police highly invasive surveillance powers in the name of counterterrorism.

"This is the beginning of a new wave of mass surveillance in Japan," the 33-year-old American said in an exclusive interview from his exile in Russia, referring to Japan's conspiracy bill, which has stirred controversy at home and abroad as having the potential to undermine civil liberties.

The consequences could be even graver when combined with XKEYSCORE, a wide-reaching U.S. data collection tool that was exposed by the former National Security Agency contractor. Snowden also gave credence to the authenticity of new NSA papers exposed by The Intercept website earlier this year that showed the secretive spy agency has already shared the surveillance tool with Japan.