Burger King Corporation, the US fast food chain, is recalling the plastic Pokémon balls given away with its "kids meals".
Its move follows reports that a 13-month-old girl suffocated when one half of a Pokémon ball covered her nose and mouth.
An 18-month-old girl is also reported to have got a half-ball stuck over her face before being rescued by her father.
The balls contain plastic Pokémon figures from the popular children's cartoon series and film.
Burger King said it was voluntarily recalling the balls as they may pose a suffocation hazard to children under three years of age.
It warned consumers to immediately take the balls away from children under three.
But they will still be distributed with Burger King's "big kids meals", intended for older children.
Although the Pokémon promotion has been running in the US since November, it has not yet reached the UK.
A spokeswoman for the UK arm said: "We will follow the US lead."