A Russian photographer who posted pictures of a rainbow flag on her Instagram account has been fined $16 for sharing an "extremist symbol", rights groups said Monday.

Russia's top court labelled the "international LGBT movement" as extremist in November, making anyone who engages in pro-LGBTQ activism or shares LGBTQ symbols liable to prosecution.

Inna Mosina, 33, was found guilty of sharing "symbols of an extremist organisation", the Perviy Otdel rights group said, citing a court in the southwestern city of Saratov. She was fined  1,500 rubles, or $16.

The group called the decision "unjust" and said Mosina published the pictures before Russia's ban on the "international LGBT movement" came into force last year.

The Kremlin has ramped up conservative rhetoric since launching its military assault on Ukraine, casting the conflict as a battle against the West and its values.

Last week, a woman in the Russian city of Nizhny Novgorod was jailed after a court deemed her rainbow earrings to be "symbols of an extremist organisation", rights groups said.