By Anthony Harrup 

MEXICO CITY--Mexican national oil company Petróleos Mexicanos will sell its 50% stake in a pipeline joint venture to partner Infraestructura Energetica Nova SAB for $1.33 billion, saying it plans to invest the money in more profitable strategic projects.

Ienova, the Mexican unit of Sempra Energy, will own 100% of Gasoductos de Chihuahua once the deal closes, which is expected in the next three months, the companies said Friday. Gasoductos de Chihuahua includes three natural gas pipelines, an ethane pipeline, a liquefied petroleum gas pipeline and an LPG storage terminal.

Pemex said the sale, which will allow it to take on other projects without taking on debt, is part of its plan to increase its operating and financial efficiency.

Under Mexico's new energy laws, the state company faces private competition in oil and gas production for the first time in its 77-year history. Pemex also has had to reduce its investment budget this year by around $4 billion because of lower oil prices, as part of broader government budget cuts.

Pemex's sales in the second quarter fell by 27% from a year before to $19.9 billion, affected by a 9.8% decline in crude oil production and a 44% drop in the price of oil.

Pemex and Ienova will maintain their joint venture in the Los Ramones Norte pipeline, which is part of a major project to carry natural gas from Texas to central Mexico. Earlier this year, Pemex sold a 45% stake in the Los Ramones II pipeline to BlackRock Inc. and First Reserve Corp. for around $900 million.

Write to Anthony Harrup at anthony.harrup@wsj.com

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