Miguel Díaz-Canel spoke to crowds in Havana the US is trying to destroy Cuba’s political system.
He said Washington wants full control through Cuba.
Díaz-Canel described US policies a form of political genocide during July 26 events.
He stressed this is a menace to the country's sovereignty.
Raúl Castro was absent from the biggest rally.
Tensions stay high because of sanctions and US political pressure.