Full coverage: G20 Hangzhou Summit

G20 summit will begin Sunday in east China's Hangzhou city. And world leaders are streaming into the city for the meeting. U.S. President Barack Obama have just arrived in Hangzhou. He is scheduled to hold talks with Chinese President Xi Jinping, on the sidelines of the summit.

U.S. President Barack Obama arrives for the 11th summit of the Group of 20 (G20) in Hangzhou, capital of east China's Zhejiang Province, Sept. 3, 2016. (Xinhua/Li Xiang)

Italian Prime Minister Matteo Renzi landed in Hangzhou in the morning. This is his second visit to China since taking office in 2014. That's also the year Italy and China established a comprehensive strategic partnership. The country was just hit by a massive earthquake, and as a platform of cooperation, the G20 summit will provide support to Rome.

Also in Hangzhou is Canadian Prime Minister Justin Trudeau. This is his first official visit to China since he took office last year. He said during this trip, he would “strive for a closer, more balanced relationship between Canada and China".

UN Secretary-General Ban Ki-moon is also in the city for the meeting, making this his eleventh visit to China as UN secretary general. Ban said this year’s summit would be a good chance to promote the early implementation of the climate change agreement, which was inked in Paris.