(Adds detail, background)
By Nadezhda Tsydenova and Tom Balmforth
MOSCOW, Oct 8 (Reuters) - Russia and China will sign a cooperation treaty aimed at combating illegal content on the Internet this month, Russia's state communications watchdog said on Tuesday, an example of deepening cooperation between the powers.
Critics have accused Russia's authorities of trying to implement Chinese-style curbs on the internet. Cooperation in this area between the two regulators could alarm proponents of internet freedom.
Roskomnadzor, the Russian watchdog, said it would sign the agreement with its Chinese counterpart at an international internet conference on Oct. 20. It said in a statement the agreement would have the status of an international treaty.
Internet controls have tightened in Russia under President Vladimir Putin and in China under President Xi Jinping.
Earlier this year, a delegation from the Cyberspace Administration of China (CAC), which oversees national cyber policy, met officials at Roskomnadzor.
The Kremlin said last week the two powers had a special relationship.
Moscow's ties with Beijing have been marked by mutual wariness in the past and some in Russia are concerned about Chinese influence in the country's sparsely populated mineral-rich east. Russia and China share a 4,200-km (2,600-mile) border.
But Russia pivoted east towards China after its ties with the West plunged to post-Cold War lows over Russia's annexation of Ukraine's Crimea in 2014. Trade ties with China have since expanded and cooperation has also broached more sensitive areas.
Last week, President Vladimir Putin said Russia was helping China build an early warning system to detect intercontinental ballistic missile launches, something only Russia and the United States possess at the moment. (Reporting by Nadezhda Tsydenova and Tom Balmforth; editing by Katya Golubkova and Philippa Fletcher)