Speaker Baleka Mbete on Friday defended the physical removal of an Economic Freedom Fighters MP from the National Assembly, saying she had a duty to protect Parliament as the opposition was trying to tarnish the legislature.

"We could not sit here in this institution and forever allow disruptions and outrageous conduct of honourable members who have come here not to work as we all do, but to come here and just push the boundaries in the process to rubbish this institution of the people," she told journalists at Parliament.

"We have never [before] had reason to call the police. It must be understood that it is incident after incident."

Mbete said Thursday's disruptions in the Assembly was plotted in advance by opposition parties and marked the culmination of a strategy that became apparent on June 17, when the fifth Parliament formally opened.

"It was in that debate that this trend that we have been observing started to show," she said.

"There is no way we are going to allow ourselves to come here and each time just be disrupted."

Asked who gave an order to briefly cut the television feed from the chamber when chaos erupted on Thursday night, Mbete did not answer directly but denied that the move constituted censorship.

"We don't have a policy of censorship, we all know the attitude of our democracy on those matters but all those issues have limitations.

"Parliament is here for a purpose and that purpose has to be protected."

Mbete said she was not only disappointed but also "depressed" by the events. She had yet to decide on any steps to be taken against opposition MPs after the Assembly saw first a lengthy filibuster and then scuffles.

"At this point we have not had those discussions as an institution. We are still actually going to go and sit and analyse in depth from different angles.

"We analyse together and then we can determine a course of action."

Mbete rejected claims by the opposition, who on Thursday chanted "you must go" at her, that she was biased because she is also the chairwoman of the ANC.

She said all MPs belonged to political parties.

When reminded that ANC secretary general Gwede Mantashe had called on the legislature to protect President Jacob Zuma she told Sapa: "He does not run Parliament!"