Cuban authorities are warning they will pull the licenses of private taxi drivers who raise fares.

The mostly 1950s-era American cars that function as collective taxis cost about 40 cents and are a key form of transportation on the island. People have complained recently of rates doubling on some routes.

The warning comes as officials say the country faces months of economic and energy restrictions due in part to the crisis in Venezuela and a reduction in the amount of oil Cuba receives from its South American ally.

Official website Cubadebate reported Friday that Havana official Isabel Hamze said government officials held an emergency meeting and agreed to take "severe measures" against drivers who raise fares. It added that fuel prices are stable so there's no need to hike rates.