By Linda Sieg
TOKYO (Reuters) - Japanese Prime Minister Shinzo Abe sent a ritual offering to Tokyo's Yasukuni Shrine on Friday, prompting sharp rebukes from China and South Korea even as Abe seeks meetings with their leaders to improve strained ties.
The shrine is seen by critics such as China, parts of which were occupied by Japan before and during World War Two, and South Korea, where bitter memories of Japan's 1910-1945 colonization persist, as a symbol of Japan's past militarism, because it honors wartime leaders convicted by an Allied tribunal as war criminals along with millions of war dead.
A group of Japanese lawmakers paid their respects at the shrine on Friday, the beginning of an autumn festival, while Abe sent a small masakaki tree, Reuters witnesses said.
There was no sign of cabinet ministers, although NHK public television said Health Minister Yasuhisa Shiozaki sent an offering. A ruling party lawmaker tweeted that three ministers planned to visit on Saturday.
China expressed "serious concern" after Abe's offering.
"China reiterates that only by Japan earnestly and squarely facing, deeply reflecting upon its history of invasion and clearly distancing itself from militarism, can China-Japan relations realize healthy and stable development," Chinese Foreign Ministry spokesman Hong Lei said in a statement.
South Korea said it deplored Abe's offering to the shrine, which it called "the symbol of glorification of Japan's colonization and invasive war".
"Japan should move forward to a bright future based on serious reflection on the past, not locking itself in the dark past," South Korea's foreign ministry spokesman said.
Expectations have been growing in Japan that Abe, who outraged Beijing and Seoul by visiting Yasukuni in person in December 2013, will be able to meet Xi for ice-breaking talks next month at an Asia-Pacific leaders' summit in Beijing.
Signs of a thaw have been growing as both sides recognize that the chill was bad for business in the world's second- and third-biggest economies and raised the risk of an unintended clash that could escalate militarily.
Prospects for a leaders' meeting, however, are clouded by China's demand for a signal that Abe not make another pilgrimage to the shrine.
"AGREE TO DISAGREE"?
A public promise not to pay his respects at Yasukuni again would be impossible for Abe, whose conservative agenda includes recasting Japan's wartime history in a less apologetic tone.
Abe has said he visited the shrine not to glorify war, but to honor those who fought and died for their country.
But he has stayed away from the shrine since his 2013 visit, instead sending offerings on key dates, seeking to tread a fine line between his conservative convictions and the diplomatic imperative to improve ties with China.
Koichi Hagiuda, a ruling Liberal Democratic Party (LDP) aide to Abe, told Reuters this month that the prime minister could put off a visit if he judged it was in Japan's national interests. Hagiuda also said Abe, now in Milan for a meeting of Asian and European leaders, was likely to refrain from visiting in person ahead of the November gathering in Beijing.
In further signs of a possible thaw, Abe and Chinese premier Li Keqiang shook hands and exchanged greetings at a dinner in Milan, the first time they have spoken directly.
China also wants Japan to acknowledge the existence of a territorial dispute over tiny islands in the East China Sea controlled by Japan but claimed by Beijing, according to Japanese lawmakers recently in Beijing.
Japanese diplomatic experts ruled out such a move but said it was possible the two sides could find a diplomatic formula to "agree to disagree" over the uninhabited islands, known as the Senkaku in Japan and the Diaoyu in China.
A slowing Chinese economy and a sharp drop in Japanese investment are main factors prompting China to rethink its relations with Japan, experts said.
Lower tension would also benefit Japanese companies doing business in China, while a meeting with Xi would be a feather in Abe's diplomatic cap. Abe has traveled to about 50 countries since taking office, but has been unable to meet Chinese or South Korean leaders during that time.
Abe has also signaled that he wants to meet South Korean President Park Geun-hye at the Nov. 10-11 Asia-Pacific Economic Cooperation leaders summit. But persistent disputes over the legacy of Japan's colonization of the Korean peninsula have cast doubts over such a meeting.
(Reporting by Linda Sieg; Editing by Dean Yates, Nick Macfie and Clarence Fernandez)