As Winston Churchill once said: "We shall fight them on the beaches, we shall fight them on the landing grounds, we shall fight on them on Twitter." Or... something like that.
Following the Canadian delegation to Nato's jibe about Russian troops not knowing their geography after 10 were caught inside the Ukraine border, the Russians have responded with their own form of cartographic raillery.
The crux of the disagreement is around the ownership of Crimea - marked as part of Ukraine on Canada's map.
Despite the fact the crisis in Ukraine is turning into an increasingly bloody civil war, it's nice to know that senior diplomats around the world still have time to throw some shade at one another on Twitter.