Argentina’s oil producers will be barred from exports unless they increase fuel supplies to address shortages in the country, Economy Minister and presidential candidate Sergio Massa said Sunday.

“If the fuel supply is not resolved by midnight on Tuesday, companies will not be able to send out export ships starting on Wednesday,” Massa told reporters in Tucuman province. “Argentines’ oil belongs first to Argentines.”

Massa added that some companies were holding onto fuel supplies on bets the government would devalue the official exchange rate after last week’s presidential elections.

The comments come amid fuel shortages that have sparked long lines at the pump and gas station closures, as the government’s dollar shortage stranded ships at sea that were waiting to import fuel.

Argentina’s oil and gas producers said in a joint statement Saturday that the fuel shortages will “normalize” in the next few days. Argentina said last week it would import 10 tanker fuel ships shipments in coming days to address shortages after a spike in demand, as well as increase refining capacity.

Argentina produces the majority of fuel it uses domestically, but is still a net importer of natural gas.

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