Venezuelan president Hugo Chavez said that he was finishing his fourth round of chemotherapy in Cuba and expressed optimism that he will not require any further treatment.
Mr Chavez spoke by phone from Havana to hundreds of supporters who gathered at the Riverside Church in New York to pray for his health.
Those in the church included Bolivian president Evo Morales and the foreign ministers of Cuba and Argentina.
“Those prayers today have great meaning for me,” Mr Chavez said in the call, which was broadcast on Venezuelan state television.
“We’re closing the fourth round of chemotherapy and with the grace of God, this will be sufficient.”
“I’m just about to finish,” Mr Chavez said. “It’s something malignant that’s turning into something benign.”
“I promise you I will live,” he said.
His supporters chanted: “No, Chavez won’t go!”
Mr Chavez underwent surgery in Cuba in June to remove a tumour from his pelvic region. Since then, he has undergone three rounds of chemotherapy, and has said this should be the final phase.
Mr Chavez has said previously that tests have shown no signs of a recurrence.
Venezuelan vice president Elias Jaua said that Mr Chavez’s health was steadily improving.
Mr Chavez “is doing well, better every day”, Mr Jaua said.