UNITED NATIONS, Rajab 15, 1437, April 22, 2016, SPA -- China and the United States, the world's top producers of greenhouse gas emissions, pledged on Friday to formally adopt by the end of the year a Paris deal to slow global warming, raising the prospects of it being enforced much faster than anticipated, according to Reuters. The United Nations said 175 states took the first step of signing the deal on Friday, the biggest day one endorsement of a global agreement. Of those, 15 states also formally notified the United Nations that they had ratified the deal. Many countries still need a parliamentary vote to formally approve the agreement, which was reached in December. The deal will enter into force only when ratified by at least 55 nations representing 55 percent of man-made greenhouse gas emissions. China and the United States together account for 38 percent of global emissions. "China will finalize domestic legal procedures on its accession before the G20 Hangzhou summit in September this year," China's Vice Premier Zhang Gaoli told the U.N. signing ceremony, attended by some 55 heads of state and government. U.S. Secretary of State John Kerry, who signed the deal said the United States "looks forward to formally joining this agreement this year." President Barack Obama will formally adopt the agreement through executive authority. --SPA 23:13 LOCAL TIME 20:13 GMT www.spa.gov.sa/w