The US has formalized its pledge to reduce greenhouse gas emissions under the non-binding agreement struck at the Copenhagen Climate Summit last month. On Thursday, the Obama administration submitted its plan to reduce emissions by 17 percent of 2005 levels by 2020. The figure amounts to just four percent of the 1990 levels used as the standard by the rest of the world. The US pledge is contingent on congressional approval. Other countries to submit their reduction targets include the Marshall Islands, which pledge to reduce emissions 40 percent. Marshall Islands Foreign Minister John Silk said, “If one of the smallest and most vulnerable island states can take action, the largest countries have no excuse not to follow our example.”