To Lam, general secretary of the Communist Party of Vietnam Central Committee, on Monday said Chinese President Xi Jinping's state visit to Vietnam will make important and great contributions to promoting the traditional friendship of the two countries and opening up a new era of development in Vietnam-China relations.To Lam made the remarks in an article published in the People's Daily, the official newspaper of the Communist Party of China Central Committee.Stressing that peace, friendship, cooperation and development have always been the mainstream of relations between the two countries, To Lam said the stable, sustainable and long-term development of Vietnam-China ties is in the fundamental and long-term interests of the two peoples.In recent years, bilateral relations have continuously reached new heights, leading to important and comprehensive achievements in various areas of cooperation, he said, adding that the two countries' diversified exchange and cooperation mechanisms in various channels and fields have further enriched and deepened the connotation of their comprehensive strategic partnership.In terms of economic and trade relations, To Lam noted that Vietnam remains China's largest trading partner in ASEAN and has become China's fourth largest trading partner globally, adding that China has become Vietnam's third largest source of foreign investment and ranks first in the number of new investment projects.To Lam called on the two sides to continue to implement the high-level exchange mechanism, and enhance the effectiveness of cooperation in areas such as diplomacy, national defense and security.He called for jointly promoting the pragmatic, in-depth, balanced and sustainable development of bilateral cooperation, and expanding cooperation areas where China has advantages and Vietnam has needs.Taking the Vietnam-China Year of People-to-People Exchanges as an opportunity, the two sides should promote people-to-people exchanges and the friendly relations between the two Parties and the two countries, as well as advance the substantive development of cultural, tourism and educational cooperation, he said.