A judge in Mexico ordered state oil company Petroleos Mexicanos not to cancel contracts with Oceanografia SA, the services provider that Citigroup Inc. says defrauded the bank of $400 million, Bloomberg News reported today. The Aug. 15 decision, released today on a Mexican judiciary agency’s website, requires Pemex to allow the Ciudad del Carmen-based company to continue working on existing projects. The ruling, which grants some requests from the mediator involved in the restructuring, also prevents Pemex from collecting collateral and payments under administrative proceedings against the company. The move will let Oceanografia keep a regular source of income while in bankruptcy and under the guardianship of the government, according to the ruling.