The Japanese ambassador to China, Uichiro Niwa, arrived in Nanjing yesterday on a three-day visit, seen by Chinese and Japanese media as a sign of improving ties between the two countries.
Ties have been tense since a Chinese trawler and a Japanese patrol boat collided near the disputed Diaoyu Islands in September.
An information official from the Japanese embassy in Beijing said yesterday the visit would serve to promote the bilateral relationship and foster economic co-operation.
There had been media speculation that Niwa's trip might pave the way for a visit to the city some time later by Japanese Prime Minister Naoto Kan, but this could not be confirmed.
Nanjing, the capital of Jiangsu province, was China's capital city during the second world war. After it fell to the Japanese on December 13, 1937, their troops killed more than 300,000 people during the month-long Nanjing massacre.
Kyodo News said Niwa would not visit the Memorial Hall of the Victims of the Nanjing Massacre. However, it reported that the fact his visit had been approved by Beijing indicated better ties.