Twenty Economic Freedom Fighters (EFF) MPs have been found guilty of all charges stemming from their heckling of President Jacob Zuma over his Nkandla home, Parliament's powers and privileges committee said on Wednesday.

EFF Chief Whip Floyd Shivambu and his colleague Mpho Ramakatsa were found guilty of seven charges each, and EFF leader Julius Malema and the party's spokesperson Mbuyiseni Ndlozi of four charges each.

The rest of the group, who chanted "pay back the money" at Zuma in the National Assembly during presidential question time on August 21, were found guilty of between one and six charges, committee chairman Lemias Mashile said.

"It has been a lengthy discussion on Monday that took us into the night. Eventually the committee reached a conclusion that the charges that the 20 members of the National Assembly are facing have been proved and these charges stick to them and they are found guilty on those charges," Mashile told reporters.

These charges range from refusing to obey an order by the Speaker to sit down or leave the chamber, to creating a disturbance in Parliament and interfering with the functions of the legislature.

Mashile said the EFF MPs would be given an opportunity on Friday to plead in mitigation of sentencing.

However, Malema made it plain that his party refused to take any part in the disciplinary process, in a submission read to the committee on October 7. He also threatened that the party would challenge in court any punishment imposed by the committee.

On Wednesday, the EFF MPs leadership could not immediately be reached for comment. They were in a sitting of the National Assembly where they and the Democratic Alliance clamoured for Zuma to appear in the chamber, from which he has been absent to answer questions since the heckling incident.

DA parliamentary leader Mmusi Maimane led the charge, demanding from Deputy President Cyril Ramaphosa to say when Zuma would "come to account".

Ramaphosa launched a spirited defence of the president and, referring to the events of August, said the fault lay with the opposition who disrespected Zuma and prevented him from answering questions by "howling and screaming and shouting".

"If you want to promote a good relationship you have to create a conducive environment for that relationship to thrive," Ramaphosa said.

"I want to call on members of the opposition to be respectful to the president." Shivambu rose to protest: "He is casting aspersions on us and really he is not assisting us." Speaker Baleka Mbete told him to sit down. She did the same with Ndlozi when he rose to call Ramaphosa out of order for pronouncing on the disciplinary process, as it was sub judice.

Mashile said the committee reached the finding of guilty through "sufficient consensus", but conceded it was not a unanimous decision. Opposition parties are on the record as saying they did not agree.

He defended the committee's decision not to call Mbete to testify, saying members believed it would be improper for her to give evidence as she had referred the matter to the committee.

Opposition party members on the committee had asked that she be called. They were also reportedly unhappy because the former and present state security ministers, Siyabonga Cwele and David Mahlobo, who tried to intervene with the EFF when they refused to leave the chamber, did not testify to the committee in person. Instead they submitted affidavits.

Mashile declined to set out the punishment that can be imposed on the EFF's members, but according to the parliamentary rules it includes suspension from the legislature for 14 working days.