The governor of Argentina's oil-rich Santa Cruz province warned on Wednesday that the withdrawal of two key concessions held by YPF was "irreversible", piling more pressure on the country's biggest energy company.
YPF, controlled by Spain's Repsol, is under heavy pressure to invest to boost production. Six provinces have already stripped YPF of concessions on the grounds of slack investment but most have been in marginal areas.
Santa Cruz Governor Daniel Peralta, an ally of the national government, said officials were maintaining "a hyper critical observation" over YPF's performance at the Canadon Vasco, Los Perales-Las Mesetas and Pico Truncado-El Cordon fields, the state news agency reported.
Canadon Vasco, Los Perales-Las Mesetas accounted for 8 percent of the company's total crude output in January and 4 percent of natural gas, government data shows.
YPF has defended its investment record and started legal action against one of the provinces.