Washington:
The US has accused Russia of sending heavy weapons, multiple rocket launchers and military hardware in support of pro-Moscow separatists in Ukraine.
"We assess that separatists in eastern Ukraine have acquired heavy weapons and military equipment from Russia, including Russian tanks and multiple rocket launchers," State Department Deputy Spokesperson Marie Harf said.
The US has information that Russia accumulated tanks at a deployment site in southwest Russia, and some of these tanks had crossed from Russia into Ukraine in the past three days, Harf said.
"In the last three days, a convoy of three T-64 tanks, several BM-21 or Grad multiple rocket launchers, and other military vehicles crossed from Russia into Ukraine near the Ukrainian town of Snizhne. This is unacceptable," she said.
"Ukraine's Interior Minister said three tanks crossed the border from Russia yesterday. Internet videos showed this same type of tank that departed southwest Russia moving through multiple cities in eastern Ukraine, including Snizhne, Torez, and Makiyivka," she said.
"Russia will claim these tanks were taken from Ukrainian forces, but no Ukrainian tank units have been operating in that area. We are confident that these tanks came from Russia," she said.
Harf said that Russia accumulated multiple rocket launchers at the same deployment site in southwest Russia, and they were also recently departed.
"Internet video has shown what we believe to be these same rocket launchers travelling through Luhansk," Harf said.
Harf earlier said the US and its European allies have encouraged Russia to support the peace plan and assist the Ukrainian President in its implementation.
Though the presidents of Russia and Ukraine have spoken, the US is highly concerned by new Russian efforts to support the separatists, she said.