We investigate the leading-twist light-cone distribution amplitudes for the
pion and kaon based on the gauge-invariant nonlocal chiral quark model from the
instanton vacuum in the presence of external axial-vector currents. We find
that the nonlocal contribution from the gauge invariance has much effects on
the pion distribution amplitudes, while it changes mildly the kaon ones. We
also study the Gegenbauer moments of the distribution amplitudes and compare
them with the empirical analysis of the CLEO data.Comment: 14 pages, 10 figure