The letter says, in part: "Ukraine is wholly committed to democratic European values, regards itself as part of the Euro-Atlantic security space and is prepared to stand up against common security threats jointly with NATO and the bloc's partners."
Kiev has also assured Brussels that Ukraine would join NATO only after "asking the opinion of the Ukrainian people."
The letter has provoked loud political debate in Ukraine. The Party of Regions is the main opponent of joining NATO. It has accused Ukrainian authorities of violating the Constitution, which describes Ukraine as a neutral state that should not join military blocs or allow the deployment of foreign troops and military bases on its territory.
The only exception is the Russian Black Sea Fleet's base, which is to be pulled out in 2017.
The Party of Regions also demands holding a referendum on joining NATO. The outcome of such a referendum is easy to predict: according to independent polls, more than 60% of the population opposes joining the bloc.
Why does Kiev want to join NATO, and why does NATO need Ukraine? And what would the consequences of Ukraine's NATO membership be for Russia?
Unlike Moscow's former allies in the Warsaw Pact and the Baltic countries, Ukraine does not see NATO as an umbrella or protection against possible aggression by "an unfriendly power."
A military conflict or the threat of military force is unthinkable in Russian-Ukrainian relations, as both countries know full well. No politicians, even those who hate Russia, have even as much as inferred this possibility.
However, Kiev, which is an inalienable part of Europe, believes that it can join the European Union only as a NATO member, and its Western neighbors support this view. Unfortunately, the practice of the past few years shows that this is true.
Joining NATO will demand sacrifices and additional efforts from Ukraine, such as fulfilling the Membership Action Plan, promoting democracy and the social status of the Ukrainian military, converting the army to NATO standards, and introducing a real, not declarative, civilian control over the country's military, among other things.
Ukraine will also have to spend large amounts to rearm its armed forces with Western equipment, because Russia will most likely stop supplying spare parts and components for the majority of Ukraine's Soviet weapons.
Kiev will have to say good-bye to many of its leading defense enterprises, notably aerospace ones, which cannot survive without Russia. NATO does not need Ukraine's defense sector, because it needs its own sector to work to its full potential. As for Russia, its politicians, including First Deputy Prime Minister Sergei Ivanov and Ambassador Viktor Chernomyrdin, have said that Russia would terminate its military cooperation with Ukraine if it joins NATO.
Additionally, Ukraine will have to provide troops for participation in NATO operations around the world, including in Afghanistan. Washington allowed Ukraine to withdraw its troops from Iraq before Yushchenko was elected president for his first term, which largely helped him to defeat Leonid Kuchma. But after Ukraine becomes a NATO member, it will have to supply its troops to fill the gaps in NATO's armor, like the other new members are now doing.
In fact, Brussels expects Ukraine to do this because many European governments and their electorates are dissatisfied with their losses in Iraq and Afghanistan. NATO also needs Ukraine as one more brake on Russia's influence in former Soviet space. If Ukraine joins the bloc, Russia will have to work hard and spend large amounts to ensure its security in the southwest, which may slow down Russia's rapid economic progress.
In addition, Ukraine is a better place for the U.S. ballistic missile systems than Poland or the Czech Republic. Military experts are confident that these systems would be deployed in Ukraine.
Lt. Gen. Henry Obering, director of the U.S. Missile Defense Agency (MDA), likes to speak about ABM cooperation between Kiev and Washington. He does not say how Kiev is doing this, but after joining NATO it will most certainly have to please its ally.
If Ukraine joins the bloc, it will control the Black Sea and hydrocarbon routes from Central Asia to southern Europe, jointly with Turkey, Bulgaria and Romania (and possibly Georgia). This group will be able to put pressure on the countries of the Caucasus, the Middle East and Central Asia that dare to displease Washington and Brussels.
What can Moscow do in this situation? First, it should not do anything at the moment. Ukraine may still fail to join NATO because anti-bloc sentiments in the country are strong, especially in its southern and eastern regions. If Ukrainians knew all the possible consequences of joining the bloc, they would never vote for it.
Second, it will not be the end of the world even if Ukraine joins NATO. Russia will have to develop relations with it and the enlarged bloc, cooperating where it fits and refusing to work jointly if it runs contrary to Russia's national interests. The Kremlin will need to be flexible, patient and wise, and above all practical.
And last but not least, Ukraine will be able to join NATO no sooner than 2017, after - and if - the military base of a non-EU country (Russia) is withdrawn from it. This is a long time during which anything can happen.
The opinions expressed in this article are the author's and do not necessarily represent those of RIA Novosti.