At a trilateral summit in Guadalajara, Mexico, Presidents Barack Obama and Felipe Calderon of Mexico, and Canadian Prime Minister Stephen Harper, committed their countries to develop policies and programmes to combat global warming. In a statement, the leaders said they supported a worldwide goal of reducing global emissions by at least 50% compared to 1990 or more recent years by 2050, with developed countries lowering emissions by at least 80% compared to that period by then. To help achieve agreed low-carbon development goals, the countries will develop comparable approaches to measuring, reporting and verifying emissions reductions, including cooperation in reporting greenhouse gas emissions throughout the region.