Russian President Dmitry Medvedev has warned that missiles could be deployed on the EU’s borders if the US pursues its missile defence plans.
In a televised statement, he said “modern weapons systems” could be deployed in Kaliningrad if Russia, the US and Nato failed to come to a deal.
He added that Moscow may opt out of the New Start arms deal agreed with the US.
Nato chief Anders Fogh Rasmussen said he was “very disappointed” by Mr Medvedev’s response.
Washington wants an anti-missile shield ready by 2020 but Moscow considers the idea a threat to its nuclear forces.
The US says the shield is intended to provide protection from the potential missile threat posed by countries like Iran.
Washington had originally intended to locate major parts of its missile defence shield in Poland and the Czech Republic under Bush-era plans.
But Russia had objected vigorously, and when President Obama took office he scaled-back these ambitions.
However, Moscow has yet to be satisfied that the revised plans do not pose a threat to its interests.
