“A great war has arrived at our doorstep — the likes of which Europe has not seen since World War II. Unfortunately, the losses in such a war will be measured not in the hundreds but thousands and tens of thousands,” Geletey wrote in a message posted on his Facebook page on Monday.
He further claimed that “hundreds of Russian soldiers and officers have permanently entered Ukraine’s (eastern) ‘black earth’ region.”
Geletey made the comments a day after alleging that Russian troops were moving in the main cities of Lugansk and Donetsk.
President Petro Poroshenko, also, told military cadets in Kiev on Monday that “the situation has aggravated in recent days – there is direct, overt aggression against Ukraine from the neighboring state.”
Ukraine’s army forces retreated from the airport of the eastern city of Lugansk as well as a nearby village on Monday after an hours-long battle against a “reinforced tank battalion of the Russian armed forces,” according to security spokesman Andriy Lysenko.
Since Kiev launched military operations to silence the pro-Russia protesters in mid-April, Ukraine’s mainly Russian-speaking regions in the country’s east have witnessed deadly clashes between pro-Moscow forces and the Ukrainian army.
Violence intensified in May after the two flashpoint regions of Donetsk and Luhansk held local referendums, in which their residents voted overwhelmingly in favor of independence from Ukraine.
Kiev and its Western allies accuse Russia of fueling the crisis in east Ukraine, but Moscow has repeatedly denied the allegations and criticized its Western neighbor for the heavy crackdown on the pro-Russia protesters in the region.