Taku Yamasaki, secretary general of the Liberal Democratic Party, left Japan on Thursday morning for a nine-day visit to five Southeast Asian countries.

LDP officials earlier said Yamasaki, who will first visit Jakarta, plans to convey and explain the intentions behind Prime Minister Junichiro Koizumi's controversial Yasukuni Shrine visit Monday to leaders of Indonesia, Singapore, Cambodia, Thailand and Vietnam.

Officials said Yamasaki also plans to hand the leaders personal letters from Koizumi and mainly discuss security issues, including Japan's possible participation in U.N. peacekeeping forces.

According to the officials, Yamasaki will hold talks with Indonesian President Megawati Sukarnoputri. It will be the first time Megawati meets a top official of Japan or its ruling parties since she took office last month, they said.

Yamasaki is expected to convey his approval of Indonesia's democratic change of power and express support for helping the country carry out reform and democratization, the officials said.

Koizumi's visit to Yasukuni Shrine has drawn strong criticism from South Korea and China because the Shinto shrine honors 14 Class A war criminals along with Japan's 2.47 million war dead.

Southeast Asia was occupied by the Japanese military during World War II.