Mexico’s Finance Ministry announced Tuesday it will launch a new financial operation to support the country’s embattled state oil company, Pemex—the most indebted energy firm in the world. The operation involves issuing “Pre-Capitalized Notes,” a form of financing designed to strengthen Pemex’s balance sheet without a direct government guarantee. The plan—part of an ongoing effort to prop up a company mired in debt, production decline, and operational dysfunction—is noticeably short on specifics.…