What are you talking about? There is nothing like this in the link you provided. It says:
The President informed that the given information was trustworthy and confirmed that the majority of the Russian military armored vehicles had been destroyed by the Ukrainian artillery at night.
http://www.president.gov.ua/en/news/30998.html
There is no backing off from his claims.
Russia’s Defense Ministry has denied Kiev’s report that it “destroyed the Russian military column” which allegedly crossed into Ukraine, saying that no such column ever existed.
http://rt.com/news/180584-border-russian-military-troops/
Somebody is lying. Time will tell.