The City of Cape Town has been granted leave to appeal a court order that in effect seals most documents pertaining to the N1/N2 Winelands Toll Highway project, ahead of a review hearing, it said on Monday.

The Supreme Court of Appeal (SCA) granted the city's application on Friday, after an initial application was dismissed by the Western Cape High Court, transport mayoral committee member Brett Herron said.

"The SCA has given us an expedited hearing date of 18 March 2015 to ensure that a final decision on this matter can be reached well before the hearing of the review proceedings," he said.

"This will assist in creating a properly informed public debate about the desirability of the proposed tolling system."

In August, the Western Cape High Court dismissed applications by the SA National Roads Agency Limited (Sanral) and its preferred bidder Protea Parkway Consortium (PPC).

The parties had applied to the court to prevent the city from filing its supplementary founding papers in an open court.

Despite dismissing the applications the court granted relief that in effect kept certain information under wraps until the court started to review Sanral's decision to toll the roads.

The city's supplementary papers included details about the toll fees, the total expected revenue, the proportion of the profits, the cost-benefit ratio and affidavits by a number of experts who evaluated tolling information from Sanral.

In May last year, the city was granted an interim interdict to halt the proposed N1/N2 Winelands Toll Highway project, which will remain in force until the review hearing.

The proposed concession route along the N1 extends from west of the R300 interchange to Sandhills. The N2 portion of the proposed toll road concession extends from west of the R300 to Bot River.

About 180km of highway in the province will be tolled should the project go ahead.