Relations between the two countries continued after the fall of the Soviet Union. The relationship gained some importance again after Vladimir Putin was elected President of Russia in 2000. Kim Jong-un also accepted an invitation to visit Russia in mid-2015. The two states share a border along the lower Tumen River (Туманная ; 두만강), which is long and was formed in 1860 when the Tsar Alexander II acquired territory ceded from Qing dynasty China in the Convention of Peking.