Prime Minister Shinzo Abe made an offering to the controversial Yasukuni Shrine during a Shinto festival in late April, a chief Cabinet official revealed Tuesday, reigniting a dispute among Japanese leaders, some who believe the act may harm foreign relations.

During a Cabinet Office press conference on May 8, Chief Cabinet Secretary Yasuhisa Shiozaki had no comment regarding the Prime Minister’s offering, according to Japanese media reports. He said Abe gave the offering privately, not formally. So it is just a matter of personal religion. I can’t say anything for it as a comment of the Japanese government.

Abe has not visited the Yasukuni shrine since he became Prime Minister last September. The shrine has been a source of contention in Asian countries because it not only memorializes over 2.5 million of Japan’s war dead, but also including 14 Class-A war criminals from World War II. China and Korea have strongly criticized the shrine and have demanded that the Class-A war criminals be separated from it.

According to reports, Abe offered a sacred sasaki potted plant in the name of Prime Minister. The plant was placed at the side of a wooden stairwell that leads to the main shrine hall during the spring Shinto festival held from April 21 to 23. The offering cost 50,000 yen ($417). He reportedly paid it with his money, not the government’s.

Foreign Minister Taro Aso said, His offering to Yasukuni has nothing to do with foreign relationships, according to business daily Nikkei Shinbum.

On the other hand, Yukio Hatoyama, Secretary General of the Democratic Party, which is a main opposition party, said according to Nikkei that his way of offering is really a cowardly action. If he wants to give service to the shrine, he should do it boldly. Actually he used his official name of Prime Minister,so we regard his action as official behavior.

Furthermore, the Japanese Communist Party showed deep concern that it might bring international criticism against Japan, not only from Asian countries.

Abe has not said whether he would visit the shrine while Prime Minister. His predecessor, Junichiro Koizumi, visited the shrine six times during his tenure, inspiring both approval and disdain.