Literally, to wave with a fence post. That is, to make a very broad hint, a wake-up call.
German Diplomatic Building in Kyiv Damaged by Russian Attack – Germany said a Kyiv building housing the German visa office had been damaged in the barrage of missiles that hit the Ukrainian capital on Monday and said Berlin would deliver the first of four modern air defense systems to Ukraine within days.
“Since the beginning of Russia’s war of aggression, these offices have not been used by our embassy,” Germany’s foreign ministry said in a tweet. “Our colleagues at the embassy in Kyiv are well.”