MOSCOW, June 25. /TASS/. Former NSA contractor Edward Snowden has twittered highly critical remarks on a new package of Russian antiterrorist laws.

He described them as "an unworkable, unjustifiable violation of rights that should never be signed."

The package of antiterrorist bills, which the State Duma endorsed on Friday, was initiated by deputy Irina Yarovaya and Senator Victor Ozerov. It contains a mandatory provision for Internet providers to store data on the transfers of information and the users’ personal data over a period of twelve months.

In addition, mobile telephony operators will be obliged to store the data on acceptance, as well transfer, delivery and processing of voice messages, texts, images, sounds, and videos for three years.

As for the most cumbersome content - the contents of messages, including graphic information, sounds and videos - will be maintained for up to six months.

If the package gets approval of the Federation Council, the upper house of Russian parliament, the bulk of the amendments will take effect only Jul8y 20, 2016. But for mobile telephony and Internet providers the data of effectuation of the law is July 1, 2018.

"Mass surveillance doesn’t work," Snowden twittered. "This bill will take money and liberty from every Russian without improving safety."

He also believes that "to store 6 months of content is not just dangerous, it’s impractical.".