Russian defence minister Mr Igor Sergeyev said today NATO expansion eastwards into the Baltics and former Soviet states could destroy a landmark treaty limiting conventional forces in Europe.
Interfax news agency quoted Mr Sergeyev as saying ties with NATO had improved since Britain's George Robertson became secretary general but potential pitfalls remained.
Any offer of membership to the Baltic states and members of the Commonwealth of Independent States (CIS), a Russian-led grouping of former Soviet republics, could severely damage ties.
"If there was such a development, NATO's military infrastructure would virtually reach Russia's borders," Mr Sergeyev said.
"And if among the new members of the alliance there were Baltic countries and CIS states, then that could destroy the Conventional Forces in Europe Treaty," he added.
Estonia, Latvia and Lithuania, which regained independence from the Soviet Union in the early 1990s, have sought to create closer links to the West by securing NATO membership. NATO is cautious because of deep Russian hostility to the move.
Signed in the dying days of the Cold War, the Conventional Forces in Europe (CFE) treaty, revised in 1999, limits the number of battle tanks, heavy artillery, combat aircraft and attack helicopters deployed and stored between the Atlantic Ocean and Russia's Urals Mountains.
Reuters