"My only regret was to campaign for Zuma, and I apologise dearly," Malema told the Star.
He also rejected Zuma's idea of a "second transition", which the Mail & Guardian reported was rejected on Wednesday by the ANC policy conference under way in Midrand.
"To wake up in the morning and announce you are now in a second transition, like you're announcing the second birthday of a child, is politically incorrect and lacks ideological clarity," said Malema.
A document on the second transition is one of the ANC's 13 policy documents under discussion at the four-day conference.
Zuma said in opening the conference on Tuesday that the second transition would make the country a "true democratic developmental state … which has a number of instruments it can use to facilitate change".
The first transition was still important because it had ushered in an era of democracy in South Africa.
"The time has come to do something more drastic to accelerate change towards economic transformation and freedom."
Zuma asked delegates to discuss the notion of a second transition when dealing with the strategy and tactics document.
"It is time to ask questions about the present and future … the last 18 years was the first transition. We are calling for a dramatic shift … to deal with the triple challenge[s] of poverty, unemployment and inequality," said Zuma. – Sapa