 In 1643, Vassili Poyarkov's boats descended the Amur, returning to Yakutsk by the Sea of Okhotsk and the Aldan River, and in 1649–1650 Yerofey Khabarov occupied the banks of the Amur.The resistance of the Chinese, however, obliged the Cossacks to quit their forts, and by the Treaty of Nerchinsk (1689) Russia abandoned her advance into the basin of the river.Although the Russians were thus deprived of the right to navigate the Amur River, the territorial claim over the lower courses of the river was not settled in the Treaty of Nerchinsk of 1689.