International Red Aid
Vidali found refuge in the Soviet Union, relocating to Moscow. Working for the International Red Aid, Vidali was sent by the Comintern to Mexico to discipline its national party, according the Mexican Communist Party. During this period, Vidali became romantically involved with photographer and communist activist Tina Modotti, who had a previous liaison with artist Diego Rivera and was then involved with Cuban communist Julio Antonio Mella, then in Mexico.