Screening and anti-screening effects in $J/\psi$ production on nuclei

Nuclear effects in $J/\psi$ hadro- and electroproduction on nuclei are considered in framework of reggeon approach. It is shown that screening regime which holds for electroproduction at $x_F \gtrsim 0.7$ and for hadroproduction at $x_F \gtrsim - (0.2\div 0.4)$ is changed with anti-screening regime for smaller $x_F$ values.