The Inkatha Freedom Party (IFP) leader, affectionately known as "Shenge", was reacting to Zuma's off-the-cuff remarks about opposition parties joining forces to table a motion of no confidence in the president in the National Assembly on Thursday.
Buthelezi had previously complained that Zuma had not responded to his letter outlining why the IFP was supporting a move to table the motion by, among others, the Democratic Alliance, the Congress of the People and the Freedom Front Plus.
Zuma said he had no problems with political alliances.
However, he implied that the parties were deceiving their voters.
The president said parties were voted into power because people supported their policies, but when they came to Parliament they aligned themselves with other parties and pushed different agendas.
"Some identities are beginning to disappear," Zuma said to applause from MPs in the ANC's benches. Opposition party MPs responded with loud heckling.
Zuma said he had not responded to Buthelezi's letter as he preferred to call for a meeting with "Shenge" if there were issues to discuss.
Buthelezi later stood up, switched on his microphone, and asked speaker Max Sisulu if Zuma would welcome a question.
Not a question
ANC MPs shouted "Ha, ha" and "No". However, Zuma accepted the invitation to be questioned.
Instead, Buthelezi started telling Zuma about how his ministers had chided him during the debate on Wednesday.
An irritated Sisulu ruled that this was not a question, and allowed Zuma to carry on with his speech.
Zuma, who was on the podium for over an hour, was clearly still battling to shake off illness.
"If I clear my throat, let it not be known that I am proud. I'm still dealing with the flu," he said as MPs and guests in the house smiled.
The public gallery was a sea of green, yellow and black – the colours of the ANC.
Members of the ANC Women's League, dressed in green and black, and others wearing ANC T-shirts packed one of the gallery bays – a place usually reserved for VIP guests like former presidents and foreign dignitaries.
MPs were more formally dressed, although not in the silks, laces and expensive materials which were on display when Zuma delivered his opening address last week. – Sapa