The Barack Obama administration will contribute another $500 million to Chrysler LLC through the end of this month as it seeks to reach an alliance with Fiat, and up to $5 billion through May to help General Motors Corp (GM) restructure outside of bankruptcy. Also, the United Auto Workers (UAW) union urged its members to lobby the White House by phone or email to ensure that workers and retirees are treated fairly in negotiations at both companies on new concessions, which are considered vital for the automakers' to survive. “We need President (Barack) Obama and his auto task force to stand up for the interests of workers and retirees in these restructuring negotiations,” the union said in an appeal on its Web site to members. The UAW represents about 26,000 workers at Chrysler and 62,000 at GM.