Russia has been negotiating its entry into the global trade body for more than 15 years.
"Our position on joining the WTO is the same, it has not changed and it is the following: the Russian Federation is ready to join on normal, nondiscriminatory conditions. We have done all that is necessary. This process has been drawn out, and this irritates us," Medvedev told journalists.
"The key thing is that this [process] does not turn into an endless story," he said after talks in Moscow with Chilean President Michelle Bachelet, who reaffirmed Chile's support for Russia's membership of the WTO.
In a joint statement released after their talks, the Russian and Chilean leaders reiterated Chile's support for Russia's inclusion in the organization.
"Chile has once again confirmed its support of Russia's future membership in the WTO," the document said. "Its participation in this organization will promote the strengthening of the multilateral system of world trade, and the development of bilateral trade and economic cooperation."
Russia has finished the necessary bilateral negotiations with 60 interested countries, but has not coordinated a number of positions of principle, including on agriculture, on export duties for timber, and on regulation of the activities of some state companies.