The local magnetic susceptibility of the spin-triplet superconductor ${\mathrm{UTe}}_2$ has been investigated by positive muon (${\mu }^{+}$) Knight shift measurements in the normal state. Three distinct ${\mu }^{+}$ Knight shift components are observed for a magnetic field applied parallel to the $c$ axis. Two of these exhibit a breakdown in the linear relationship with the bulk magnetic susceptibility ($\chi$) below a temperature $T^{*}\sim 30\mathrm{K}$, which points to a gradual emergence of a correlated Kondo liquid. Below $T_{\mathrm{r}}\sim 12\mathrm{K}$ linearity is gradually restored, indicating relocalization of the Kondo liquid quasiparticles. The third Knight shift component is two orders of magnitude larger, and despite the $c$-axis alignment of the external field, scales with the $a$ axis $\chi$ above $T_{\mathrm{r}}\sim 12\mathrm{K}$. We conjecture that this component is associated with magnetic clusters and the change in the temperature dependence of all three Knight shift components below $T_{\mathrm{r}}$ is associated with a change in magnetic correlations. Our findings indicate that prior to the onset of superconductivity the development of the itinerant heavy-electron fluid is halted by a gradual development of local U $5f$-moment fluctuations.

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• Kondo effect
• Magnetic interactions
• Spin-triplet pairing