Japan may provide more medical assistance to China to help treat victims of chemical weapons left behind at the end of World War II, the top government spokesman said Monday.

"We are considering conducting (more) medical research" in China following a dispatch of medical professionals to the area in northeastern China where a fatal accident occurred in August, Chief Cabinet Secretary Yasuo Fukuda told reporters.

The poisonous gas leak, which killed one and injured 43 others, occurred as containers of mustard gas, left behind by retreating Japanese forces, were uncovered at a construction site in Qiqihar, Heliongjiang Province.

Japan said Sunday that it has agreed with China that Tokyo will pay 300 million yen over the incident in Qiqihar.