The Russian-Chinese military and technical cooperation became more active in 2011, including due to its aviation component, assessed at $1 billion, the head of Russian state arms exporter Rosoboronexport said. "China's share in Rosoboronexport's order portfolio has exceeded 4%. Our ties have gone up in 2011 - the value of aviation and aircraft construction contracts, including for the delivery of the Al-31F and Al-31FN engines, has nearly reached $1 billion," Anatoly Isaikin told the Kommersant business daily. Isaikin attributed a decrease in bilateral military and technical cooperation since 2006 by high growth rates of the Chinese military and industrial sector. The official said intergovernmental agreements envision that big contracts could be signed in the future.