Several Western Cape mayors vowed on Thursday to join the fight against e-tolling in the province.

"We, the mayors of the DA-led municipalities of Stellenbosch, Theewaterskloof, Drakenstein, Breede Valley, and the Winelands District want to express our unconditional opposition to Sanral's proposed N1 and N2 Winelands toll project," they said in a statement.

"We wholeheartedly support the City of Cape Town in its attempt to obtain an interdict to stop this project and will soon formally meet with them to discuss our involvement."

The mayors said the proposed tolls would have dire consequences for locals and the poorer communities would be largely affected.

The tolls would also badly affect the agricultural sector.

"Farmers already spend millions each year to transport their loads to and from the Cape Town harbour.

"The planned toll will be a tremendous additional financial burden to this industry and the many people it employs under difficult financial circumstances," said the mayors.

They criticised the SA National Roads Agency Limited (Sanral) for not disclosing the cost of the project and not providing the public with a full understanding of the financial implications.

The mayors said taxpayers had already spent large amounts of money in maintaining the province's roads.

Sanral served the city with a notice on March 6 indicating that it intended resuming the project.

On Monday, city officials filed an application to halt the project.

Transport and roads mayoral committee member Brett Herron said the urgent interdict application had been set down for May 16 and 17 in the Western Cape High Court.

The city had previously filed an urgent interdict application in November 2011.

Sanral agreed at that stage to take no further steps towards introducing the project pending the review application yet to be decided upon by the Western Cape High Court.

It also undertook to provide the city with 45 days' notice of its intention to start working on the project.

Herron said Sanral agreed not to conclude a concession agreement before June 1, 2013.