Petrol firms including Shell Italia, Eni, Tamoil Italia and Esso Italia again increased their prices on Monday following a series of hikes, Corriere della Sera reported.
The average national price for unleaded petrol is now at up to €1,836 a litre and €1,739 for diesel.
Unions Faib Confesercenti, Fegica Cisl and Anisa Confcommercio said in a joint statement that the Italian government was "indifferent" to their complaints over the prices.
Flavio Zanonato, the industry minister, said the government was preparing an appeal to the oil companies to avoid further hikes over the summer, a period when consumption rises, Corriere reported.
He called on the firm to take into account “the situation of the country”, which is steeped in recession.
Zanonato added that the hikes were mainly due to increases in crude-oil prices.
Talks are due to take place between unions and oil firm representatives on Wednesday in a bid to revive negotiations.
The strike will begin at 10pm tonight, ending at 6am on Friday.