Moscow, April 7 (RHC)-- U.S. whistleblower Edward Snowden has said that the U.S. government is putting American citizens at risk by the National Security Agency’s spying activities.

“The NSA has the greatest surveillance capabilities that we’ve ever seen in history. Now, what they will argue is that they don’t use this for nefarious purposes against American citizens,” Snowden said in an interview with HBO's "Last Week Tonight." Ed Snowden added: "In some ways, that’s true, but the real problem is that they’re using these capabilities to make us vulnerable to them and then saying: ‘Wow, I have a gunpoint at your head, I’m not going to pull a trigger. Trust me.’”

The former NSA contractor is currently in Russia after leaking thousands of the agency’s documents over surveillance programs. In June 2013, the U.S. whistleblower revealed that the NSA has been collecting the phone records of millions of Americans and foreign nationals as well as political leaders around the world.

Following the revelations, Ed Snowden fled the United States to avoid espionage charges. In August 2013, Russia granted him asylum.