Foreign Minister Sergei Lavrov said NATO's eastward expansion and U.S. plans to deploy missile defense elements in Poland and the Czech Republic cannot be justified by security concerns, RIA Novosti said Wednesday.

Lavrov said the country would have to take "appropriate measures" if Ukraine were to join NATO.

The foreign minister also called on NATO countries to ratify an updated version of the Soviet-era Conventional Forces in Europe Treaty aimed at regulating the deployment of non-nuclear weapons on the continent.