Islands standoff dominates ties

Uichiro Niwa, the newly retired Japanese ambassador to China, left Beijing quietly on Wednesday morning as questions remain over strained Sino-Japanese ties.

Niwa, 73, witnessed ups and downs in the two countries' relations over the past two years and four months, with the most turbulent moments coming during the territorial dispute over the Diaoyu Islands in the East China Sea.

Tokyo ran into a major diplomatic standoff with Beijing after the Japanese government illegally "purchased" part of the islands in mid-September.