  In this paper, we build upon the successes of the ultraviolet (UV) completion
of the Starobinsky model of inflation. This involves an extension of the
Einstein-Hilbert term by an infinite covariant derivative theory of gravity,
which is quadratic in curvature. It has been shown that such a theory can
potentially resolve the cosmological singularity for a flat, homogeneous and
isotropic geometry, and now it can also provide a successful cosmological
inflation model, which in the infrared matches all the predictions of the
Starobinsky model of inflation. The aim of this note is to show that the
tensor-to-scalar ratio is modified by the scale of non-locality, and in general
a wider range of tensor-to-scalar ratios can be obtained in this class of
model, which can put a lower bound on the scale of non-locality for the first
time as large as the O$(10^{14})$ GeV.
