ENERGY

Conoco, Canadian Firms Offer Natural Gas Plan to Mexico: The groundbreaking proposal was made by Conoco Inc. and Calgary-based companies Nova Corp. and Noranda Inc.’s Canadian Hunter Exploration Ltd. to develop a natural gas field in northern Mexico. But the proposal, given to state-owned Petroleos Mexicanos several months ago, is still in “preliminary” stages of discussion and awaiting action by Mexico, Conoco spokeswoman Sondra Fowler said. The proposal calls for Conoco, a unit of DuPont Co., and the two other firms to produce gas from huge fields that extend south across the Rio Grande from the state of Texas. Mexico’s constitution forbids foreign ownership of energy resources, but Fowler said Conoco’s proposal is structured as a “service contract,” which may be legally permissible.