Uranium dioxide (UO2) is the standard fuel used in light water reactors (LWRs). However, it has a low thermal conductivity that ultimately limits its performance both during normal operation and in accident conditions. Adding a material with high thermal conductivity is a potential approach to enhance the thermal conductivity of UO2. Forming an interconnected structure of high-conductivity material can significantly enhance the overall thermal conductivity of the composite. Molybdenum (Mo) has been used as an additive material in UO2 composites previously. A new method for the fabrication of interconnected UO2−Mo composites using pre-sintered UO2 granules to improve the continuity of Mo channels was investigated in this study. UO2–10 wt% Mo composites were produced using UO2 granules and 1073 K and 1473 K pre-sintered UO2 granules, followed by spark plasma sintering (SPS) of the mixtures at 1473 K for 5 min. The composites were characterised using scanning electron microscopy and X-ray diffractometry and their thermal conductivities were measured by the laser flash method and compared with a reference UO2 pellet. At a maximum measurement temperature of 1073 K, a 52 % increase in thermal conductivity was observed in the composites containing UO2 without pre-sintering, and UO2 pre-sintered at 1073 K. The increase was 31 % for composites manufactured from UO2 pre-sintered at 1473 K. These results suggest that higher temperature pre-sintering may be detrimental to forming interconnected Mo structures.