Mexico's largest company lost 125.5 billion pesos in the fourth quarter of 2018, compared with 299.7 billion pesos from the corresponding period the year before.

Pemex registered revenues of 1.68 trillion pesos, up from 1.39 trillion in 2017, including 407 billion pesos in the final quarter.

Fourth quarter hydrocarbon and crude production was down on the previous year yet sales nonetheless increased by 2.3 percent.

That was mostly due to "export sales increasing five percent as a result of the recovery in crude prices," said Pemex.

The company owes more than $100 billion while its Fitch credit rating was dropped to negative in October, creating greater uncertainty among investors.

The government said earlier this month it would inject 107 billion pesos into the company to boost production but experts say that figure might not be enough.

Production has dropped by almost 50 percent in 15 years from 3.4 million barrels a day in 2004 to 1.8 million.

The previous government under Enrique Pena Nieto had tried to reverse that trend by opening the market to the private sector, ending Pemex's 80-year monopoly.

But new leftist President Andres Manuel Lopez Obrador criticized that strategy and in December cancelled the last oil auctions planned for 2019, announcing that he would launch his own plan to boost Pemex's production.