Japanese Prime Minister Junichiro Koizumi yesterday expressed his "deep reflections and heartfelt apology" for Tokyo's wartime colonization and aggression towards China and other Asian neighbors.

"Our country has caused great damages and pain to people in many countries, especially our Asian neighbors, through colonization and invasion," Koizumi said in a statement.

Japan's relations with some of its Asian neighbors have hit the lowest in years because of disputes about whether Japan has properly atoned for its past aggressions. The issue has stirred opposition to Tokyo's bid for a permanent seat on the U.N. Security Council.

Fueling the grievances are Koizumi's controversial visits to Tokyo's Yasukuni war shrine and his government's approval of textbooks that critics say whitewash wartime atrocities such as the Rape of Nanjing, in which Japanese troops massacred as many as 300,000 people while taking the Chinese city in 1937.

Tensions have also been stoked by disputes between Tokyo, Beijing, Taipei and Seoul over resource-rich islands off their coasts, and Japan's running argument with China over gas drilling in a contested area of the East China Sea. Concerns over communist North Korea's nuclear weapons program have also increased regional friction.