It's popped up on bus stops, road signs and even a pram in Russia: a "Z" sign to whip up support for what Moscow describes as its "special military operation" in Ukraine.

The campaign takes as its motifs the distinctive "Z" and "V" markings that Russia displayed in white on the flanks and noses of tanks and armoured vehicles that invaded Ukraine on Feb 24.

The letters - as well as a long diagonal stripe - were assumed to be...