Russian President Vladimir Putin has signed an updated national security paper describing Nato's expansion as a threat to the country.
The paper says Russia's "independent domestic and foreign policy" has triggered a "counter-action" from the US and its allies.
It accuses these countries of striving to dominate global affairs.
The conflict in Ukraine, which began in 2014, has led to a sharp deterioration between Russia and the West.
The updated National Security Strategy signed by President Putin on Thursday is the latest in a series that are critical of Nato.
In 2014 Russia announced it was altering its military doctrine to take account of the Ukraine crisis and Nato's presence in eastern Europe.
Kremlin adviser Mikhail Popov said at the time that Nato's enlargement in recent years meant the alliance was getting closer to [Russian] borders and presented an "external threat" to his country.
Albania and Croatia joined Nato in 2009. In 2011, the alliance recognised four aspiring members - Bosnia, Georgia, Macedonia, and Montenegro.
Russia's National Security Strategy is updated every six years.
The new version says Russia is strengthening its military "on the background of new threats to national security that have a complicated and interlinked character".
The paper says Nato's recent build-up of military potential around Russia's borders constitute "violations of norms of international law".
The BBC's Diplomatic Correspondent Bridget Kendall says that Mr Putin is determined through his interventions in Syria and Ukraine to wield his country's military clout, so that the world in general and the United States in particular realise that Russia is an equal partner whose interests must be accommodated.
Our correspondent says Mr Putin wants the West to acknowledge Russia's right to treat its post-Soviet neighbours as part of its sphere of influence, free from links to Nato or any other Western-dominated alliance.
He is on the lookout for levers to weaken Europe's ties with the US, our correspondent says, in the hope of one day turning Russia into Europe's main strategic partner.