The contribution of active Galactic nuclei to the diffuse gamma-ray background

We consider the emission of high-energy to very-high-energy gamma -rays in radio-quiet active Galactic nuclei (AGN) or the central regions of radio-loud AGN. We use our results to estimate the gamma -ray flux from the central regions of nearby AGN and then to calculate the contribution to the diffuse gamma -ray flux from unresolved AGN.