A multiparty delegation of Diet members began on Monday a three-nation European tour, starting in Germany, to study war-contingency rules in those countries.
The group consists of five members of the House of Representatives committee on proposed legislation to define Japan's response to foreign military attacks.
They include the committee chairman, Tsutomu Kawara, a member of the Liberal Democratic Party and former Defense Agency chief, and Eisei Ito, a member of the Democratic Party of Japan and former parliamentary vice minister of construction.
The other members are Fumio Kyuma, an LDP member and former Defense Agency chief, Kazuyoshi Kaneko, an LDP member and former parliamentary vice minister of construction, and Masao Akamatsu, a member of New Komeito.
The group will hold talks with officials in Germany, Poland and Switzerland, wrapping up its tour Sunday, officials of the parties said.