Malema, who was being interviewed on the BBC's World Service in London on Monday evening, said his expulsion was being contested by structures of the ANC, IOL reported on Tuesday.
He told BBC the ANC's elective conference in Mangaung in December would be used to overturn it. "When we remove president [Jacob] Zuma in December, it will be an automatic overturning of that decision," he was quoted as saying.
Malema said people were still committed to him even though he had been expelled by the ANC, because he was "leading a revolution in South Africa for economic emancipation". This was "close to the hearts of the people" of both South Africa and Africa, according to the report.
He said his relationship with ANC veteran Winnie Madikizela-Mandela worried the party. "I am still very close to her, which worries some in the ANC who thought that by expelling us they would succeed in isolating us, and they have not succeeded."
According to the report, Malema said former president Nelson Mandela would be "very happy" with him as, while still young, Mandela had changed an ANC "of gentlemen" into a "fighting force".
Sky News also talked to Malema on Tuesday.
Last week, Malema – in an interview with the Sunday Telegraph – admitted that he had not seen his expulsion coming. "I was very shocked because I know the ANC to be a very patient organisation, especially with the youth," he said.
He said Zuma was to blame because he wanted to get rid of the youth league firebrand for highlighting the "institutionalised mediocrity" of his administration. He also accused the president of "stealing" his ideas.
Last week, Zuma told the ANC's national policy conference that economic transformation was needed to match the political one. He explained that if the ruling party failed to take immediate action, poverty-stricken South Africans would lose their patience.
"That's the impatience we've been speaking about but people have not wanted to listen, saying we're just a group of young people who are suffering from excitement," Malema said.
"Maybe our expulsion was precisely for this purpose, so that those ideas could shine through." Malema voiced regret over backing Zuma to replace former president Thabo Mbeki in 2007.
"He was presented to us as a man of the people who would not continue with neo-liberal economic policies," he said.
"But we realised very quickly we had made a mistake. He became worse and worse and abused state power, used his influence for personal benefits."
He told the paper that Zuma's ANC would shame Mandela. "President Mandela had so much love and respect for the people. It would be wrong to even compare him with what we have today," he said. – additional reporting from Sapa