  Persistent current and low-field magnetic susceptibility in single-channel
normal metal rings threaded by a magnetic flux $\phi$ are investigated within
the tight-binding framework considering long-range hopping of electrons in the
{\em shortest} path. The higher order hopping integrals try to reduce the
effect of disorder by delocalizing the energy eigenstates, and accordingly,
current amplitude in disordered rings becomes comparable to that of an ordered
ring. Our study of low-field magnetic susceptibility predicts that the sign of
persistent currents can be mentioned precisely in mesoscopic rings with fixed
number of electrons, even in the presence of impurity in the rings. For perfect
rings, low-field current shows only the diamagnetic sign irrespective of the
total number of electrons $N_e$. On the other hand, in disordered rings it
exhibits the diamagnetic and paramagnetic natures for the rings with odd and
even $N_e$ respectively.
