Speaking in the National Assembly during question-and-answer time, Inkatha Freedom Party MP Mkhuleko Hlengwa, asked Ramaphosa whether he was ready to call out the ANCYL for spreading "fake news".
In January, the ANCYL accused both Ramaphosa and Finance Minister Pravin Gordhan of trying to collapse South African Airways (SAA) so a company linked to him would benefit financially. Ramaphosa said he was in the process of engaging the youth league on the matter.
"I have told them that the matter they raised publicly was a lie, was a fabrication and as you say, fake news, because there is no truth that I am conducting business with SAA or any other company," he said.
The deputy president said he disposed of all his shares in the Shanduka group in 2014, and therefore has no conflict of interest to declare under the executive ethics code.
"I did not leave business to come into government business, to come and conduct fraudulent business in government," Ramaphosa told MPs.
"I hold the view that if you want to make money, make money in business, do not come and make money dealing with government entities."