Morales, who arrived in Cuba over the weekend for talks with President Raul Castro, was due in New York on Tuesday for the annual meeting of the UN General Assembly.
Before leaving Cuba on Monday, he told state-run Prensa Latina he would devote his UN speech to “some reflections on the crisis of capitalism, and on the inhuman interventions like the one in Libya.”
He said the UN Security Council’s approval of military action against the Libyan regime of Moamer Kadhafi was “a shame for humanity.”
“What Security Council? I would say it is an insecurity council,” he said.
Morales and fellow leftist, President Hugo Chavez of Venezuela, have been among the most outspoken opponents of the NATO-backed uprising against Kadhafi, insisting it was a Western grab for Libya’s oil reserves.
Morales arrived in Havana late Saturday with Chavez, who was returning to Cuba to undergo a fourth round of chemotherapy treatment for cancer.
He also met with Cuba’s aging revolutionary icon Fidel Castro, who has rarely been seen in recent months amid rumors of ill-health.
But Morales told reporters the 85-year-old former president is “recovered, very strong, walking normally and with lucid reflections, as always.”
Cuba posted new photos of Fidel Castro on government-run news websites earlier this month, in an apparent effort to quiet rumors that the former president and revolutionary icon was dying or dead.
Castro, hero of the revolution that swept dictator Fulgencio Batista from power in 1959, remains a communist icon, five years after handing over power to his younger brother Raul, following a medical crisis.