In a video message presented during a hacking conference, former U.S. spy agency contractor Edward Snowden called for the development of new technologies that could prevent surveillance programs around the globe. Snowden said that he would devote his time to promoting encryption technologies that would allow people to communicate anonymously. He appeared on Saturday via video link from Moscow to the New York City conference, known as Hackers On Planet Earth, or HOPE.

"You in this room, right now have both the means and the capability to improve the future by encoding our rights into programs and protocols by which we rely every day," he said. "That is what a lot of my future work is going to be involved in."

Snowden escaped the United States after leaking documents that detailed massive U.S. surveillance programs at home and abroad. Currently located in Russia, he has requested an extension to his Russian visa, which is due to expire. The United States wants Russia to send him home to face criminal charges.