Negotiations made no progress on Tuesday as Royal Dutch Shell Plc and union leaders haggled over a new wage contract for U.S. refinery workers who have been on strike for three days, the union said. The two camps have been at an impasse since the United Steelworkers union (USW) called walkouts early on Sunday for the first time since 1980 at nine plants with about 10 percent of U.S. refining capacity, saying Shell left the negotiating table when talks broke down.