 This prompted an increase in the Russian authorities' attention to their borderland; in 1756, the Orenburg Governor Ivan Neplyuyev even proposed the annexation of the Lake Zaysan region, but this project was forestalled by Chinese successes.Concerns were raised in Russia (1759) about the (theoretical) possibility of a Chinese fleet sailing from Lake Zaysan down the Irtysh and into Western Siberia.A Russian expedition visited Lake Zaysan in 1764, and concluded that such a riverine invasion would not be likely.