Moscow on March 14 denounced Poland's defense minister for saying the 2010 plane crash that killed Poland's president was a Russian act of terrorism.
Official investigations by Poland and Russia have determined that the crash that killed Lech Kaczynski near Smolensk, Russia, was an accident caused by the error of pilots trying to land in heavy fog.
Polish Defense Minister Antoni Macierewicz has previously suggested the crash was an assassination, but he went further than that in a lecture this weekend.
"What happened near Smolensk was aimed at depriving Poland of its leadership, which was on a path of leading our nation to independence," Macierewicz said. "We were the first victims of terrorism in the 1930s, and through Smolensk, we can say that we were also the first major victim of terrorism in a modern conflict, which is unfolding before our eyes."
Russia's Foreign Ministry described Macierewicz's statements as absurd.
"Irresponsible statements by Mr. Macierewicz aimed at further destabilization of the already difficult relations between our countries aren't in sync with earlier signals from Warsaw suggesting a desire to develop pragmatic cooperation," it said.
Kremlin spokesman Dmitry Peskov described his charges as "unfounded, biased."