That's complete bollocks, because all those CO₂ emissions are proportional to the amount of fuel, and the power density of nuclear fuel is such that the total amount is indeed tiny.
Solar panels and wind turbines also require emitting CO₂ for their manufacture, and it turns out that they emit more than nuclear, fuel included.
Additionally, while enrichment requires a lot of energy, to spin turbines or fuel gas separation, it's electrical energy, and in France for instance it's nuclear energy fueling enrichment.