Fugitive US intelligence leaker Edward Snowden on Thursday asked Russian President Vladimir Putin a question on the extent of Moscow's surveillance activities during a phone-in session. Snowden, who has been given asylum in Russia, asked the question in English via video. It was not clear if the video was recorded or was live. Putin replied that the kind of "mass eavesdropping" on the population that Snowden exposed in the United States was impossible as Russia's special services were under strict control.