Japanese Prime Minister Shinzo Abe has sent a ritual offering to the Yasukuni Shrine, seen by critics as a symbol of Japan's past militarism, media reported on Monday, a move likely to further strain ties with China and South Korea. The offering from Abe, who visited the shrine in December, was sent just before U.S. President Barack Obama's three-day visit to Japan, which begins on Wednesday. Japanese media said Abe would not visit the shrine in person. Fourteen Japanese leaders convicted as war criminals by an Allied tribunal after World War Two are honoured there, along with Japan's war dead. Tensions with China were likely to increase further after a Chinese maritime court on Saturday seized a ship owned by Japanese shipping firm Mitsui O.S.K.