Mexico plans to halt crude oil exports in 2023 as part of President Andres Manuel Lopez Obrador’s nationalist goal of self-sufficiency in fuel production.

Petroleos Mexicanos, the Mexican state-owned producer known as Pemex, will reduce daily crude exports next year by more than half to 435,000 barrels before phasing out sales to foreign customers the following year, chief executive officer Octavio Romero said during a news conference in Mexico City on Tuesday.

The ambitious — and some say improbable — endeavor is part of Lopez Obrador’s drive to expand homegrown production of gasoline and diesel that Mexico now mostly buys from U.S. refiners. Like many major oil-producing nations, Mexico lacks the processing capacity to convert its oil bounty into fuels and other end-products.