March 21 (Bloomberg) -- Petroleos Mexicanos, the third- biggest oil supplier to the U.S., needs to enter alliances with several companies to help it develop deep-water oil fields, said Mexico Energy Minister Georgina Kessel.

Pemex has held negotiations with Brazil's Petroleo Brasileiro SA and Norway's Statoil ASA, said Kessel, who is also chairman of Pemex's 11-member board. She spoke today in an interview with Radio Formula in Mexico City.

Her comments come three days after Pemex warned of a ``critical'' situation because oil and natural gas reserves have dropped by half since the beginning of 2002. The company estimates it has almost 30 billion barrels of oil in Gulf of Mexico deep waters. Deep-water drilling has gone slow because of Pemex's lack of experience, the cost and a worldwide dearth of drilling rigs.

``It's important that we find the mechanisms so we can enter these types of associations, so we can achieve exploitation in deep water,'' Kessel said. It's also important that development ``not be with only one company,'' she said.

``Normally, companies work in groups so they can contribute technology, so they can contribute the best solutions for the problems of developing these types of fields,'' Kessel told Radio Forumla.

Pemex needs to push its exploration and production into waters more than 500 meters deep to make up in the long term for a production decline at Cantarell, the world's third-largest oil field.

Gas Finding

Pemex has ordered three-dimensional seismic mapping of the ocean floor in deep water and has sunk four exploratory wells in waters as deep as 900 meters. The water depth at the offshore giant Cantarell is about 60 meters.

In one of the deep-water exploratory fields, called Lakach, Pemex discovered a reserve of natural gas, possibly the company's fourth largest gas-only field, according to an e- mailed report today. Many times, both gas and oil are found together.

The Lakach field contains 200 million of equivalent barrels of possible gas deposits, Pemex said. Three other gas-only fields may rank above Lakach, the Jose Colomo, Reynos and Chilapilla fields, Pemex said. Those were discovered three decades ago.

Cantarell Output

Cantarell, which accounted for 55 percent of Pemex's crude production last year, declined 12 percent in 2006 to 1.79 million barrels per day. The company forecasts it will decline 15 percent this year. Ghawar in Saudi Arabia is the world's largest oil field, followed by Burgan in Kuwait.

Cantarell's daily production in February was 1.567 million barrels, an 18 percent drop from 1.912 million barrels in February 2006 and a 1.5 percent slide from 1.591 million barrels in January, according to the Energy Ministry's Web site.

In February, Pemex's daily crude production fell almost 5 percent to 3.15 million barrels a day from 3.31 million barrels a year ago. Crude exports dropped 10 percent to 1.77 million barrels a day from a year ago. Pemex sells about 80 percent of its oil exports to the U.S.

On March 2, Mexican President Felipe Calderon said Pemex expanded a technology agreement with Petroleo Brasileiro, known as Petrobras, although he didn't give details of the accord.

Petrobras has pioneered deep-water drilling, helping expand its daily crude production to 1.8 million barrels from 1 million in 1998. Petrobras has drilled in waters more than 2 kilometers deep, including the U.S. Gulf of Mexico and West Africa.

Mexico's constitution reserves the oil, gas and refinery industries for the state, barring private and foreign companies from investing directly.

Both Petrobras and Statoil are government controlled. On Sunday, Mexican President Felipe Calderon called for shoring up Pemex while avoiding privatization.

To contact the reporters on this story: Thomas Black in Monterrey at tblack@bloomberg.net

Last Updated: March 21, 2007 18:01 EDT