Mexico's Pemex expects to explore and assess its shale oil and gas portfolio with the hope of starting mass development in 2023-2024, the company's exploration director said Friday.

The company is currently drilling its first two shale exploration wells since the energy reform was approved, Juan Antonio Escalera told S&P Global Platts at the sideline of the Mexican Petroleum Congress in Acapulco.

"I don't want to speculate on output numbers, but without a doubt, we have the potential to increase production in the midterm and long-term," Escalera said.

Shale is key for Mexico future oil and gas production as half of the country's prospective resources, over 60 billion boe, are locked in shale formations.