Senior Bush administration officials told a Senate committee that while human activities are largely responsible for recent climate changes, mandating drastic reductions in greenhouse gas emissions is not the appropriate response for the United States. Instead, the administration aims to reduce the greenhouse gas intensity of the U.S. economy by 18% over the next 10 years. However, critics argue this intensity approach would still allow emissions to increase faster than recent trends. The administration report to the UN described U.S. climate policies and measures but stopped short of pledging to stabilize or reduce overall greenhouse gas concentrations as called for in the UN Framework Convention on Climate Change.