Inkatha Freedom Party MP and national spokesperson Mkhuleko Hlengwa called on government to halt fuel price levies, joining pleas made by the opposition DA, the ruling African National Congress itself and civil rights body OUTA.
He said in a statement the party would hold its own national day of action against what it called the "escalating cost of living". The central event would be a march, taking place in August.
In the statement, Hlengwa criticised the ANC and National Assembly Speaker Baleka Mbete for a recent response to a request from the party to discuss the matter in Parliament. He said the ANC was "twiddling [its] thumbs" instead of taking action against fuel levies.
"In her reply to the IFP, Speaker of Parliament Ms Baleka Mbete outright refused to deem this matter as one of national importance and therefore all IFP structures will participate in protest action to highlight the plight of millions of South Africans," said Hlengwa.
Hlengwa said the IFP National Executive Committee called for the suspension of the fuel levies, until such time as the economic situation in the country improved and the rand strengthened.
"The NEC is of the view that an overhaul in pricing adjustments is required to offer our people a better deal.
"In this regard, the IFP will launch a National Petition to mobilise South Africans and our structures in calling on government to take action," he said.
President Cyril Ramaphosa has given ministers in the economic cluster a two-week deadline to come up with measures to ease the burden of high fuel prices and the VAT hike on already struggling consumers.
However, he has added that while the matter was urgent, he did not want to "raise anybody's hopes".