A Japanese cabinet member paid homage at a controversial shrine for war dead, the 67th anniversary of Tokyo's defeat in World War Two, a move likely to further strain relations with China and South Korea.
Bitter memories of Japanese militarism run deep in China and South Korea and, despite close economic ties, relations with Beijing and Seoul have become increasingly fraught recently.
Bickering over rival territorial claims to rocky, uninhabited islands are the latest sign of how the region has yet to resolve differences over its past.
National Public Safety Commission Chairman Jin Matsubara visited Yasukuni early on Wednesday, although Prime Minister Yoshihiko Noda had urged his cabinet to stick to his stance of avoiding such visits. Many in the region see Yasukuni as a symbol of Japan's past militarism since 14 Japanese wartime leaders convicted as war criminals by an Allied tribunal are honoured there along with other war dead.
Wednesday's visit was the first by a cabinet minister since Noda's Democratic Party swept to power in 2009, promising to forge warmer ties with the rest of Asia. Pilgrimages by then-Premier Junichiro Koizumi to Yasukuni during his 2001-2006 term in office fuelled anger in both China and South Korea.
Another minister has said he wanted to pay his respects at the shrine and was expected to do so later in the day. Their defiance was another sign of Noda's weak grip on his fractious party, which has recently suffered defections over his signature plan to raise the sales tax and other policy differences.
Japan's ties with South Korea, where resentment over its 1910-1945 colonization of the peninsula remains strong, took a sharp turn for the worse after South Korean President Lee Myung-bak visited an island -- known as Dokdo in Korea and Takeshima in Japan and near potential seabed gas deposits -- claimed by both countries last Friday.
Relations with China, where memories of Japan's occupation of large parts of the country in the 1930s and 1940s still rankle, have also been strained recently by renewed bickering over uninhabited islands in the East China Sea that are near potentially huge oil and gas resources.