A chilling warning has been issued to the United States - the real battle against you has not started yet. That is the message on an audio tape purportedly made by Osama bin Laden's right-hand man, top al Qaeda official Ayman al-Zawahri. The voice on the tape warns Washington that it will pay a high price if it harms any of the detainees it is holding at Guantanamo Bay in Cuba. And it issues this threat. "We tell America only one thing," the voice says. "What you have suffered until now is only the initial skirmishes." The tape was broadcast by the Dubai-based Arabic television channel Al Arabiya, which identified the voice as that of Zawahri. **PHOTO CAPTION*** Ayman al-Zawahri, (Photo by Al-Jazeera Satellite Channel)