CANBERRA, July 22 (Reuters) - Australia said on Thursday that prison sentences for two Australian aid workers found guilty of military espionage in Yugoslavia had been reduced and deeply regretted that their convictions had not been overturned after months of diplomacy. Foreign Minister Alexander Downer insisted the CARE Australia workers were innocent and urged Yugoslav President Slobodan Milosevic to grant them clemency. Downer confirmed earlier media reports that aid worker Steve Pratt‘s sentence had been reduced from 12 years to eight and colleague Peter Wallace‘s from four years to one year. The pair‘s Yugoslav colleague, Branko Jelen, had his original six-year sentence reduced to three years, a Department of Foreign Affairs and Trade spokeswoman said. "The government deeply regrets the decision of the Yugoslav Military Court of Appeal, confirmed this evening, not to allow the appeals by Steve Pratt and Peter Wallace against their convictions," Downer said in a statement. "We are very disappointed, although not overly surprised, at the decision of the court to let the findings of guilt stand against the two men, but in each case to reduce the length of sentence," he said. "It is totally unacceptable that these two innocent men still face lengthy prison sentences," Downer said. The three CARE workers were detained on the Yugoslav-Croatia border on March 31, a week after NATO bombing raids over Yugoslavia began. They were initially charged with spying but were sentenced last month under a new charge of passing military secrets to their superiors in Canberra. Australia would continue to marshal the support of the international community and do everything possible to secure the care workers‘ release, he said.