Consumer advocacy groups on Friday asked the Administrative Court to suspend the hike in Don Muang Tollway toll rates planned from Sunday.
The petition was jointly submitted by the Foundation for Consumers and Association of Confederation of Consumers Organisation, who pointed out that tollway fees were originally due to be scrapped altogether in 2014.
The court was considering the petition, said Saree Ongsomwang, secretary-general of the Foundation for Consumers.
The groups asked for an injunction to halt the hike, which would impact consumers, until a final court ruling is handed down in the Don Muang Tollway dispute, said Ms Saree.
On Thursday, the consumer protection groups petitioned Prime Minister Prayut Chan-o-cha to intervene in the matter, she said.
"We are deeply disappointed in the Department of Highways, which has done nothing to address the matter since the Central Administrative Court ruled in 2015 to nullify a cabinet resolution on the Don Muang Tollway concession," she said.
All toll fees were due to be lifted when the previous tollway concession ended in 2014. However, the fees remained in place after concessionaire Don Muang Tollway Plc inflated its losses to justify a 20-year extension of its concession, Ms Saree claimed.
Along with the concession extension, the company was also granted the authority to adjust the toll rates without seeking approval from any state agency, she said.
"The department has not even tried to protect the public interest or consumers," she said.