The Honglujing Stele, which is about 3 meters wide, 1.8 meters tall and 2 meters thick, sits in virtual seclusion in the Japanese imperial palace as a "trophy" of the Japanese army who took it from Lushun in northeastern China's Liaoning Province after the 1904 war between Japan and Russia.

The stele is the only one known to belong to the Tang Dynasty (618-907) in northeastern China. It indicates that the first king of the Bohai Kingdom (698-926), a mysterious state during the Tang Dynasty, was conferred with the title by the Tang emperor.

Few people, including Japanese researchers, have been allowed into the imperial palace to study the stele. Zhang Yongnian and Wang Weiming, deputy directors of the Tang Honglujing Stele Research Association obtained some pictures of the stele from the Japanese imperial palace in July 2005.

Set up in 2004, the association is the most authoritative non-governmental organization on Honglujing stele study. Luo Zhewen, a famed ancient architecture expert, serves as head of the association.

Over the past two years the non-government association has been promoting study exchanges on the stele between Chinese and Japanese scholars and celebrities, such as Ikuo Hirayama, president of Japan-China Friendship Association.

Unlike what some media report said, the imperial palace of Japan has never refused further contact with Chinese researchers, and it is hopeful that the 'historical problems' surrounding the Honglujing Stele will be settled in "a cooperative and friendly way", according to the research association.

Some historical records said Bohai Kingdom was a regime founded mainly by the Mohes, a minority nationality in northeast China and forefathers to the Manchus.

With limited historical records, Japanese and Chinese archaeologists have not been able to figure out the exact date when the stele was taken to Japan, but it was widely believed to be sometime between October 1906 and April 1908.