Venezuelan President Hugo Chavez says 24 Sukhoi fighter jets have been delivered to Venezuela - and are ready to defend his country from "imperialist" aggressions. Chavez claims the US Navy's Fourth Fleet poses a threat to Venezuela, and he's vowing to push forward with a multibillion-dollar arms buildup aimed at dissuading a possible US military strike. "They're for defensive purposes, we're not going to attack anybody," Chavez said Sunday of the Russian-made jets. The Fourth Fleet was active during World War II but was dissolved in 1950. The U.S. Navy announced it would re-establish the fleet to direct naval forces in the Caribbean and Latin America. US officials deny Washington has designs on Venezuela.