Pietermaritzburg – More money may need to be spent on Nkandla to install additional security, Police Minister Nathi Nhleko said on Tuesday.This was because public scrutiny had compromised Zuma's safety, he said.“The security experts must go back to assess the extent of vulnerability and how the president has been exposed,” Nhleko told Parliament’s ad hoc committee on Nkandla in Pietermaritzburg.“We won't know how much it will cost before this exercise is done. But [with] the security issue, we will arrive at a different conclusion because of the re-evaluation.”The committee, comprised of ANC, DA, ACDP and NFP members, was expected to visit Nkandla on Wednesday. The so-called security upgrades to Zuma’s private home have so far cost taxpayers R246m. EFF and Cope MPs have refused to be part of the committee.Nhleko on Tuesday repeated much of what he said at the release of his own Nkandla report on May 28.He said the amphitheatre and soil retention wall, visitors’ centre, “firepool”, kraal and culvert, were all security features and maintained that Zuma did not have to pay for these.This contradicted Public Protector Thuli Madonsela’s own findings - released in March 2014 - that Zuma should pay for those features not related to security, like the pool and the amphitheatre.Nhleko said presidents did not decide on the extent of their protection and how their homes should be secured.'Nkandla is prone to fire'He dismissed criticism by DA Chief Whip John Steenhuisen that having to investigate the man who appointed him was a conflict of interest.“If your view is that I have arrived at my conclusion because I have been appointed by the president, then it's fine. Just because you are appointed by the president, it does not mean we owe the president favours,” Nhleko said. The “firepool” was necessary due to the uThungulu district municipality’s erratic water supply, and the prevalence of fires in the area. “Nkandla is prone to fires. At some point an old-age home burnt down and a boarding school burnt down.”He said all state homes had a visitors’ centre, so it was nothing out of the ordinary. According to the engineers, the amphitheatre was intended to function as a retaining wall, at the base of which was an emergency assembly area.“For purposes of functionality, they themselves refer to it as an amphitheatre,” he said.Meanwhile, Cope called on opposition parties on the committee to boycott the Nkandla visit.“It is our view that this visit, following the scandalous ‘Nhleko report’, is a mere ploy to sanction further expenditure on the President’s homestead at Nkandla,” spokesperson Dennis Bloem said in a statement.In going along, the opposition was lending credibility to a process that had already been predetermined and which would be settled by a vote in favour of the ruling party.