Cape Town - National Assembly Speaker Dr Frene Ginwala on Wednesday strongly defended her role in the debacle over the controversial arms deal, and appears set to sue UDM leader Bantu Holomisa for defamation.

In an open letter to the media and diplomats last month, Holomisa accused Ginwala of, among other things, dereliction of duty and bias because of her "interventions" in Parliament.

Closing debate on Parliament's budget vote in the Assembly on Wednesday, Ginwala said the United Democratic Movement and its leader had not used the opportunity in a special parliamentary debate on the matter on May 15 to substantiate the allegations.

"The author will soon have the opportunity to substantiate his allegations, though in a different venue," Ginwala said.

Asked for reaction, Holomisa, who was not present in the Chamber during the debate, said there was nothing new in what Ginwala had said. He would not retract his statements.

Until Ginwala served summons on him, he would not worry about it -- he was not scared by her. She could go to court, but he would ask the same questions there as he had in Parliament, Holomisa said.

In a hard-hitting speech which she largely used to answer criticisms raised by opposition parties, Ginwala - who did not attend the May debate - defended her membership and leadership role in the ANC.

"I want to make clear that my membership of the ANC or its leadership is not negotiable," she said to applause from ANC benches.

"I have been honoured by members of the ANC who chose to entrust me with the task of assisting in leading their organisation. Only the membership of the ANC will determine when I should relinquish that responsibility."

Ginwala said an assumption was made all too often in debates and public discourse that membership of a political party automatically impaired one's capacity to be impartial or to judge issues on their merit.

"It would appear that the absence of debates and decades of intolerance of any freedom of thought and association has led to a diminished capacity to appreciate or recognise principle, integrity and critical examination of ideas and issues as factors that guides one's judgment."

What was surely relevant in this context was to assess whether any particular judgment or action was motivated by party political advantage, Ginwala said.

"The critical factor in considering the conduct of any Speaker, honourable members, is not a perceived conflict between parliamentary responsibility and party loyalty, but gauging specific actions in the context of the responsibility placed on the office-bearer by the Constitution or the rules (of Parliament)."

Ginwala said she would take advantage in Wednesday's debate of a suggestion by Leader of the Opposition Tony Leon, that "having stepped off my throne, I enter `the hurly-burly of contested politics' ... it is not a path I intend to pursue hereafter."

She said she had often argued - on Commonwealth and other platforms - that in emerging democracies a Speaker needed to have a voice in the councils where the process of transforming society and its institutions were debated.

This was to help shape the legislature in accordance with fundamental democratic values and principles.

"I am not alone in holding this view. The (British) Empire has passed, and most of us cannot afford to wallow in colonial nostalgia and try to emulate what the House of Commons does, but should rather focus on what South Africa needs," she said to further applause from government benches.

Ginwala was particularly critical of Democratic Alliance Chief Whip Douglas Gibson, saying she had been surprised to read in Hansard that he claimed there had been "a number of occasions, and more recently, when the duality of roles of the Speaker has led to very unfortunate consequences".

Gibson had further said "this has led to some shocking incidents which have weakened Parliament instead of strengthening it".

Ginwala said she could not help asking why someone who professed a commitment to strengthening Parliament had not felt it necessary to raise these "shocking incidents until a Parliamentary debate was precipitated by another party ... Honourable Gibson, you really should try and explain your silence when Parliament was being weakened".

Gibson retorted that he had not been silent.

Referring to remarks made earlier this year by the chairperson of Parliament's standing committee on public accounts, Dr Gavin Woods, Ginwala said it was very clear Woods had a view on the Constitution and rules of Parliament - and in particular the relationship between the National Assembly and committees -- which differed from the ones she had stated in her speech, as well as of the functions of the Speaker.

"Any genuine concerns should have been raised in the Chairpersons' Forum , or brought to the rules committee. But here again, the forum of the media and generating publicity has been elevated above the use of parliamentary channels to resolve differences."

Ginwala ended her speech on a conciliatory note, thanking all MPs and whips for their co-operation during the past year... "let us now move forward together".

No other speakers in the hour-and-half debate referred to the issue, except for ANC Deputy Chief Whip Geoff Doidge, who, in the opening speech, said Holomisa had made "unsubstantiated remarks" about Ginwala.

Ginwala sat next to Deputy President Jacob Zuma in his front bench during the debate, before walking to the podium to make the closing address.

With acknowledgement to Sapa and News24.