UNITED NATIONS, Sept 10 (Reuters) - U.N. Secretary-General Antonio Guterres urged the United States and China on Friday to prevent any problems between the superpowers from harming cooperation to combat climate change ahead of the U.N. COP26 climate change conference next month. Ties between the world"s two biggest economies have been languishing at their lowest point in decades over issues ranging from human rights to transparency over the origins of COVID-19. "We understand that there are problems in the relations between the U.S. and China, but those problems do not interfere with the needs of both the U.S. and China to do everything possible to make sure that the COP is a success, independently of the relations between the two," Guterres told reporters. During a visit to China last week by U.S. climate envoy John Kerry, Chinese Foreign Minister Wang Yi said climate change was an "oasis" in China-U.S. relations but could not be separated from broader disputes. U.S. President Joe Biden and Chinese leader Xi Jinping discussed climate change during a phone call on Thursday. Xi said that if "core concerns" on both sides were respected, breakthroughs could still be made in the area of climate change. The COP26 meeting in Glasgow, Scotland, is seen as a critical chance to win more ambitious country-by-country commitments on achieving net-zero carbon emissions by 2050 and keeping the global average temperature rise to well below 2 degrees Celsius this century. "We need a stronger engagement of the U.S., namely in financing for development, for climate-related development issues, mitigation, adaptation, and we need an additional effort from China in relation to emissions," Guterres said on Friday. "But ... we are talking about a multilateral process in which all countries must commit themselves, based on their own engagement with climate action," he stressed.