From: "Russia-NATO relations - Wikipedia"
"In response to a March 2009 suggestion by Polish foreign minister Radosław Sikorski that Russia join NATO, the Russian envoy to NATO, Dmitry Rogozin, stated that Russia had not ruled that out as a future possibility but that it instead preferred to keep practical limited cooperation with NATO, adding that Russia wanted to be NATO's "partner" provided that Georgia (with which Russia had a war the previous year) and Ukraine did not join the alliance."
"For a long time, Russia has opposed the eastward expansion of NATO. After the fall of the Soviet Union and the dissolution of the Warsaw Pact, Russian President Boris Yeltsin launched a transition to a market economy. The reforms, however, also brought high unemployment, inflation, and crippled the Russian military. Nonetheless, Washington went ahead with expanding its military alliance to include former Soviet states. Yeltsin's objections, including letters of protest to the Clinton administration and to leaders of France, Germany, and the United Kingdom, were easily ignored, given the other difficulties Russia was already facing. "
"As NATO's expansion continued under the U.S. president George W. Bush, Russia's opposition would also continue under Vladimir Putin, who would eventually intervene in Georgia and Crimea. While not excusing Russia's acts of aggression, a number of Western scholars and officials have long voiced concerns that Russia would view NATO's expansion as unfriendly at best, and a threat to its security at worst, especially if the alliance ends up surrounding the country in the most ambitious version of its expansion plans. The disregard for Russia's concerns and warnings, such as Yeltsin's letters and Putin's statement at the 2007 Munich security conference, has been described as a policy and strategic blunder."