LIMA, Peru: Chief negotiator Domingo Palermo has cut off negotiations with Tupac Amaru rebels holed up in the Japanese ambassador's residence, saying he wants a "clear sign" from the captors before he will meet with them again, according to Lima's El Comercio. Has Fujimori's government turned to the hard line? "We're going to leave them in there until they get bored," a high government official told The Associated Press. Palermo has met directly with the rebels only once, a December 28 move that freed 20 hostages. But since the release of seven more last Wednesday, the 74 still held captive have waited in vain for additional progress, as the government has refused the rebels' demands for more direct talks. Palermo's recalcitrance revived fears that the standoff is headed toward a violent end. Javier Diez Canseco, an opposition congressman released after five days as a hostage, said the stalemate was becoming "extremely dangerous" because it strengthened the position of military factions in the government that favor the use of force. The rebels have retained their bargaining power with a select group of hostages, including Peru's foreign minister, five congressmen, the former Supreme Court president, the ambassadors of Japan and Bolivia and a younger brother of Fujimori. But the President seems unwilling to blink. Even as a shot heard at the compound Tuesday was unexplained, the next breakthrough in the three-week test of wills could be truly shattering.