[en] Using molecular dynamics simulations, we study the structural properties of body-centered cubic (BCC) and body-centered tetragonal (BCT) phases of U–Mo alloys. The local positions of uranium atoms in the BCC phase correspond to the BCT structure. Thus, the BCC lattice exhibits cubic symmetry only on the scale of several interatomic spacings, and it is therefore more correct to denote the high-temperature state of U–Mo alloys as quasi-BCC. This structural feature occurs for pure uranium as well. This fact is the possible origin of the difficulties encountered in the description of the BCC phase of pure uranium by ab initio methods.