“The number of (Russian) tanks at bases located along our border has tripled,” Poroshenko said in a televised interview with Ukrainian television networks on Tuesday.
He added that “the number of units that have been deployed along our border — what’s more, along its full length — has grown dramatically.”
Poroshenko highlighted that the military buildup meant that Ukraine is “under threat of full-scale war with Russia.”
The Ukrainian president didn’t give Russian troop numbers, but said the information on the military buildup was based on intelligence reports.
He said that the numbers of Russian troops in Crimea had tripled since the Black Sea region of Crimea re-integrated with Russia in 2014.
Poroshenko went on to say that authorities will take all necessary steps to release Ukrainian sailors, who were detained at the weekend when Russia seized three Ukrainian vessels off the Crimean coast.
“Immediately at night, I ordered a phone conversation with the President of Russia Putin. We did not receive response and I had to address to the German Chancellor (Angela Merkel) so that she can talk to Putin on immediate release of Ukrainian servicemen and Ukrainian ships,” he pointed out.
On Sunday, Russian warships fired upon the Ukrainian navy ships Berdyansk and Nikopol and the tug boat Yana Kapu, ramming at least one vessel and wounding several crew members.
Ukraine said it was a Russian “act of aggression”. Moscow said the ships had illegally entered its waters.
Ukraine says the ships had been trying to pass through the Kerch Strait, which is a waterway with strategic significance and the only access to the Sea of Azov, shared between the two countries.
Moscow has clarified that Russia reserves the right to defend the waters east of Crimea as an integral part of its territory. The Black Sea peninsula in southern Europe rejoined Russia in 2014.
The reunion of Crimea has been a sticking point in the relations between the two countries.
Both Moscow and Kiev accuse each other of harassing each other’s shipping in the area.