Mr Duvenhage said Outa had challenged the South African National Roads Agency (Sanral) and the Treasury in court to prove their calculations. "They couldn’t. So we argued that this therefore needs review. When the review starts, that is when we will unpack what the costs really are," Mr Duvenhage said.

The government has appealed against Judge Prinsloo’s ruling and his orders to the Constitutional Court on the grounds that he had overstepped the authority of the courts and interfered in the legitimate work of the executive.

On Friday, Outa criticised Mr Gordhan and the Treasury for their failure to provide real figures to the public.

During a briefing on the project by Deputy President Kgalema Motlanthe and five Cabinet ministers the previous day, Mr Gordhan would not say how much cash Sanral was losing each month due to the interdict against tolling. Instead, he quoted ratings agency Moody’s estimate of R270-million a month, and said "other estimates" put Sanral’s monthly losses at R500-million a month.

Mr Gordhan said this money would most likely be transferred to Sanral through a special appropriation bill. It would come out of the current fiscus and would not lead to a bigger than anticipated budget deficit.

Mr Fuzile said that, based on information collected from the gantries over the past three weeks, the economic effect of tolls on users was not as high as had been previously expected. In a bid to soften the blow for regular users, the government had set a cap of R550 a month per user.

"Our information is that less than 5% of users are reaching that cap. Toll fees for most people are about R250 a month or below."