We investigated the impact of uranium (U) on Arabidopsis thaliana seed germination and on the early stages of seedling development. Using an in vitro device, we demonstrated that uranyl ion had a very low impact on Arabidopsis seed germination but had a drastic effect on the development of Arabidopsis seedlings. We showed that the two soil bacterial strains Microbacterium sp. ViU2A and Stenotrophomonas bentonitica BII-R7, which are able to tolerate high concentrations of U, strongly reduced the toxic effects of the metal on the seedling development. This protective effect is specific to these soil bacteria, as E. coli was not able to protect seedlings. The analysis of the distribution of U between Arabidopsis seedlings and soil bacteria showed that the protective effect of the bacteria was due to their ability to sequester U either by biosorption at the level of the cell surface and/or by intracellular or extracellular biomineralization. This study reveals that these bacteria are very good candidates for use in phytoremediation strategies in the case of phytostabilisation of U-polluted soils. They would be also useful to limit the contamination of the food chain by U because they would limit the entry of this toxic element in crop plants.