Significantly, even though this year marks the 25th anniversary of a peace and friendship treaty between the two countries, there has been no exchange of visits by top leaders. Similarly, last year, which marked the 30th anniversary of the establishment of diplomatic relations, also went by without such visits, although Mr Koizumi had planned a trip to Beijing. Those plans were aborted after his visit to the controversial shrine.

A summit meeting of sorts was arranged at the end of May, when both Mr Koizumi and President Hu Jintao were in St Petersburg.

At the time, Mr Koizumi emphasised the need for the two countries to enhance political exchanges, including at the top leadership level. Mr Hu was noncommittal, although he diplomatically promised to work together with Japan towards this goal.

That goal was not achieved. What did transpire were exchanges at the ministerial level, including visits by the two countries' foreign ministers.

The August 12 anniversary was marred by an accident the preceding week, in which several dozen Chinese in Heilongjiang province were injured - one fatally - by poisonous chemicals left behind by the Japanese army. Forty-three people were treated in hospital after one of five drums of mustard gas found on a construction site was accidently opened.

Japan used chemical weapons in China during the second world war, and acknowledges abandoning 700,000 such weapons and munitions in China at the end of the war. In the 58 years since then, more than 2,000 Chinese have fallen victim to these weapons.

Up to now, Japan has not accepted legal liability in such incidents. This time, however, the Japanese government acknowledged responsibility and pronounced the accident 'extremely regrettable'. However, it remains unclear whether Japan will compensate the victims.

If Japan does agree to provide compensation, it would mark a step forward towards a resolution of historical issues.

Japan maintains that the compensation issue has already been settled because China waived the payment of war reparations when the two countries established relations in 1972. However, China maintains that individual victims have the right to ask Japan for compensation.

From the Chinese standpoint, the most important issues are historical ones. Thus, the Chinese foreign ministry's website, in discussing some sensitive issues between the two countries, put the 'issue of history' first, ahead even of the Taiwan issue.

Japan, however, focuses on economic exchanges. Thus, Mr Koizumi, in his meeting with Mr Hu, emphasised Japan's interest in taking part in the construction of a high-speed train link between Beijing and Shanghai.

'Japanese industrial circles are strongly interested in this project,' Mr Koizumi said. Again, however, Mr Hu was noncommittal, saying China had not decided whether to introduce a magnetic levitation or a rail system.

Historical issues look set to continue to beset the relationship. Last year, a government panel recommended the construction of a secular memorial as one way of avoiding disputes over visits by Japanese leaders to the Yasukuni Shrine. However, the Japanese government has just decided not to earmark funds in the next fiscal year for the construction of such a facility.

Other issues in the relationship include China's suspicions about Japanese intentions to upgrade its military.

Part of the purpose of Mr Ishiba's visit is to alleviate Chinese concerns over Japanese efforts to increase its security role in the region and the world.

China is also unhappy over Japan's interest in setting up a missile defence system in collaboration with the US. The Chinese fear such a system may be extended to provide Taiwan with an antimissile umbrella.

Frank Ching is a Hong Kong-based journalist and commentator