  The measurement of a non-zero value of the 1-3 mixing angle has paved the way
for the determination of leptonic CP violation. However the current generation
long-baseline experiments T2K and NOvA have limited sensitivity to delta_{CP}.
In this paper we show for the first time, the significance of that atmospheric
neutrino experiments in providing the first hint of CP violation in conjunction
with T2K and NOvA. In particular, we find that adding atmospheric neutrino data
from the ICAL detector at the India-based Neutrino Observatory (INO) to T2K and
NOvA results in a two-fold increase in the range of delta_{CP} values for which
a 2 sigma hint of CP violation can be obtained. In fact in the parameter region
unfavorable for the latter experiments, the first signature of CP violation may
well come from the inclusion of atmospheric neutrino data.
