By Nandita Bose and Prak Chan Thul PHNOM PENH (Reuters) -U.S. President Joe Biden told Asian leaders on Sunday that U.S. communication lines with China would stay open to prevent conflict, as the first of three summits of world leaders this week ended, with tense talks almost certain in the days ahead. Biden during an address to the East Asia Summit in Cambodia, said the United States would “compete vigorously” with Beijing while “ensuring competition does not veer into conflict”, stressing the importance of peace in the Taiwan Strait. Biden also called on Myanmar’s military rulers to follow a…