The gas fields are located on the borderline of the two countries' economic zones. Beijing refuses to recognize the line and is developing the deposits, much to Japan's discontent.
"We share a determination to solve this problem at an early stage. We will try to swiftly solve this issue," Yasuo Fukuda said at a meeting with Wen Jiabao on the second day of his four-day visit to China.
Fukuda, whose visit has already brought a thaw in tense bilateral relations, is meeting with Hu Jintao later Friday in preparation for the Chinese leader's visit to Japan next spring.
Trade between the two countries hit around $200 billion in 2006 and continued to rise in 2007. China is Japan's largest trade partner, while Japan is China's third-largest trade partner.
