Moscow's surprise announcement added a new and threatening new layer of tensions ahead of NATO's two-day summit that starts Thursday in Wales and will see Ukraine's beleaguered leader Petro Poroshenko personally lobby US President Barack Obama for military help.
The Ukrainian president's appeal for European assistance in the face of Russia's alleged dispatch of crack troops into the separatist east of his ex-Soviet country was effectively cast aside by EU leaders meeting over the weekend in Brussels.
The New York Times reported the rapid-response unit would be supported by new NATO members such as Poland that were once Soviet satellites but now view Russian President Vladimir Putin with fear and mistrust.
Moscow's answer to NATO's intentions was instant and furious.
The Russian national security council's deputy secretary Mikhail Popov said the mooted Western defence plan was "evidence of the desire of US and NATO leaders to continue their policy of aggravating tensions with Russia".
"I have no doubt that the question of the approach of NATO members' military infrastructure to our border, including by an expansion of the bloc, will remain as one of the foreign military threats to Russia," he said.
Defence Minister Sergei Shoigu said in separate comments that Russia's armed forces would be given added muscle with the deployment of 230 new military helicopters and jets by the end of the year.
