By Jan Strupczewski BRUSSELS (Reuters) - A planned meeting between the leaders of Germany, France, and Greece on Wednesday was in doubt as Greece's reform proposals to unlock new funding to ward off a debt default fell well short, European Union officials said. Chancellor Angela Merkel, President Francois Hollande and Prime Minister Alexis Tsipras were to have met on the fringes of a summit of EU leaders and heads of state and government of Latin American countries in Brussels, to clinch a political agreement on technical proposals submitted earlier by Greece.