TOKYO (Reuters) - Pakistan insisted on Tuesday that the courts would decide the fate of an American detained on murder charges, even after it was revealed he was a CIA contractor whom Washington says enjoys diplomatic immunity. The case of 36-year-old Raymond Davis, a former US special forces officer, has strained the already-uneasy alliance between the United States and Pakistan, who are supposed to be united in the face of militants waging a war in Afghanistan. Davis killing of two Pakistani men in Lahore last month has inflamed anti-US sentiment in Pakistan, effectively giving the government little choice but to prosecute him in court. His trial for murder begins on Friday, February 25. The United States, however, says Davis has diplomatic immunity and should be released immediately. The President has already stated that the matter is in the court and we will wait for the court decision in this case, Farhatullah Babar, a spokesman for President Asif Ali Zardari, told Reuters during an official visit to Japan. Regardless of whether he now turns out to be a CIA employee, the matter will be decided by the court. Davis was secretly working for the CIA and scouting a neighborhood when he was arrested, according to the British newspaper the Guardian. Raymond Allen Davis, 36, had been working as a CIA security contractor and living in a Lahore safe house, according to former and current U.S. officials who spoke on condition of anonymity because they werent authorized to speak publicly about the incident. The Obama administration insisted that Davis had diplomatic immunity and must be set free.