Ford Motor Co. is backing off ambitious plans to improve the fuel efficiency of its SUV lineup 25 percent by mid-decade, citing financial constraints and unfavorable business conditions, according to the Detroit News. The promise, made in July 2000 by former Ford CEO Jacques Nasser, touched off a public relations battle with rival General Motors Corp., which quickly vowed to top Ford's fuel-efficiency gains. Because of changing business conditions, Ford said "it's going to be extremely difficult" to achieve the fuel efficiency goals Ford established for its SUVs in 2000, according to the News. At the time, Ford's SUV models averaged 18 miles a gallon -- well below the target of 23 mpg. The company still hopes to boost the average fuel economy of its car and truck fleet between 20 percent and 30 percent by 2010, according to the News.