A top Russian general on Friday said Poland's deal with the United States to set up parts of a missile defence shield on Polish territory lays it open to a possible military strike, a Russian news agency reported.
Col-General Anatoliy Nogovitsyn, deputy chief of the general staff, told Interfax that Russian military doctrine would allow for a possible nuclear strike.
Poland agreed on Thursday to host elements of a US global anti-missile system after Washington agreed to boost Poland's own military air defences.
"The USA is engaged in an anti-missile defence for its own government, and not for Poland. And Poland, in deploying (elements of the system) opens itself to a military strike. That is 100 percent," Interfax quoted Nogovitsyn as saying.
Nogovitsyn said Russia allows nuclear weapons to be used in circumstances defined by its current security doctrine.
The Russian government revamped its national security doctrine in 2000, broadening the range of conflicts in which nuclear weapons could be used.
"It is written clearly: We will use it in instances against governments that have nuclear weapons; against allies of countries with nuclear weapons, if they somehow enable them," he said.
Washington says the missile system is aimed at protecting the United States and its allies from long-range missiles that could in the future be fired by Iran or groups such as al Qaeda. The Kremlin has long said that was untrue, and has opposed the shield as a threat to Russia.
The 10 interceptor missiles to be based at a site in northern Poland compare with Russia's own nuclear arsenal of more than 5,000 ballistic warheads. In agreeing to deploy elements of the US missile shield, Poland "becomes an actionable object.
Those targets are destroyed in the first order," Nogovitsyn said. Tension between Moscow and Washington has risen in the past week, since Georgia's attempt to re-take its separatist region of South Ossetia by force provoked a massive counter-attack by Russia.