I discuss the calculation of the
direct CP-asymmetry in $D\to \pi^+\pi^-$ and $D\to K^+K^- $ decays
with the method of QCD light-cone
sum rules. The main result is the upper limit for the difference of
the two asymmetries $\left|\Delta a_{CP}^{dir}\right| < 0.020\pm
0.003\%$ which is significantly smaller than the recent measurement of
this quantity by the LHCb collaboration.