Lawmakers from the Democratic Party of Japan will launch a group this week aimed at promoting economic ties between Japan and China amid souring bilateral relations at the political level, they said Sunday.

China's ambassador to Japan, Wang Yi, plans to attend a meeting Tuesday to mark the group's launch, they said. Key members will include former Prime Minister Tsutomu Hata and former Hokkaido Gov. Takahiro Yokomichi.

The group of politicians from the main opposition party plans to send a delegation in mid-December to China to exchange notes of cooperation with an affiliate of the Chinese Communist Party's International Liaison Department, they said.

They decided to set up the group aside from the existing group of Diet members from various parties seeking to promote Japan-China friendship, currently headed by former Foreign Minister Masahiko Komura of the ruling Liberal Democratic Party, as the liaison affiliate asked the DPJ about the possibility of serving to promote bilateral economic exchanges, they said.

Hata, who has some channels in China, has negotiated with the Chinese side toward formulating the group since last year, they said.

One DPJ lawmaker said China may have felt it difficult to get along with the LDP because of Prime Minister Junichiro Koizumi's visits to Yasukuni Shrine. Koizumi is also LDP president.