The Democratic Alliance (DA) will not take part in a "secret process" to cover up President Jacob Zuma's financial liability regarding the security upgrades to his private home in Nkandla, the opposition party said on Sunday.

"We will not be co-opted, behind closed doors, into agreeing to a sanitised version," DA parliamentary leader Mmusi Maimane said in a statement.

"The R246-million spent on President Zuma's private residence is a public crime that needs to be dealt with publicly, in a transparent and open manner."

He said during meetings with National Assembly Speaker Baleka Mbete this week it was agreed that the Nkandla ad hoc committee would reconstitute in order to deal with Police Minister Nathi Nhleko's determination and report on the security upgrades.

In a report released in March last year, Public Protector Thuli Madonsela said Zuma had unduly benefited from the non-security upgrades to his private Nkandla residence, which totalled R246-million.

She recommended that Zuma pay back "a reasonable percentage of the cost".

However, during an answer session in the National Assembly on March 11 Zuma flatly denying personal wrongdoing and any obligation to repay state money spent on his home.

Zuma said he faced no criminal charges over the project, and was under no pressure to reimburse the state because at this stage it was still up to Nhleko to decide whether he was liable to repay any portion of the sum.

Nhleko's decision was only due at month's end, he added.

According to City Press on Sunday, Mbete wanted Parliament to receive a sanitised version of the latest report.

She reportedly offered opposition party leaders a confidential briefing by Nhleko in return for them agreeing to handle the Nkandla report in secret before an edited version was presented in the National Assembly.

However, some opposition parties had described the offer as "flawed and dubious" and refused to be "complicit" in keeping details of the latest report on Nkandla secret.

Maimane said the Nkandla debacle had gone on for too long and the DA was waiting for Nhleko's public determination of how much Zuma owed for the upgrades.

"The DA will not be part of any secret process to cover up President Jacob Zuma's financial liability for the taxpayer-funded upgrades to his private residence at Nkandla," he said.

"For too long, President Zuma has evaded responsibility for allowing the maladministration of taxpayer money, which should have instead been used to improve the lives of South Africans."