Countries around Asia are honouring their dead and calling for peace, as they mark the 60th anniversary of the end of World War II in the Pacific.
Emperor Akihito took part in a solemn service of remembrance
In Japan, Prime Minister Junichiro Koizumi said his nation felt "deep remorse" for the aggression shown towards its neighbours during the war.
Commemorative services are also taking place in other Asian nations.
But across the region, many still feel that Japan has yet to fully face up to, and atone for, its wartime actions.
The war in the Pacific, which finally ended on 15 August 1945, killed millions of people from the jungles of Burma and the beaches of Singapore and the Philippines, to the cities of China and Japan and the seas of the Pacific.
Japan has been heavily criticised for the brutality of its soldiers in the countries it annexed during the war - and especially for its treatment of civilians in China.
In a written statement, Mr Koizumi admitted that Japan had "caused great damages and pain to people in many countries, especially our Asian neighbours, through colonisation and invasion.
"We will not forget the terrible lessons of the war, and will contribute to world peace and prosperity," he said.
Shortly afterwards, Mr Koizumi joined Emperor Akihito and Empress Michiko for a nationally televised service.
They bowed deeply before a memorial to the country's war dead that had been set up on a white stage.
Exactly 60 years after Emperor Hirohito formally surrendered, asking his people to "bear the unbearable" and accept defeat, his son Emperor Akihito expressed the hope that Japan would never again wage war.
"In view of history, I sincerely wish that the ravages of war will never be repeated," Emperor Akihito said.
Despite Mr Koizumi's apology and the repeated calls for peace, many Asian nations continue to feel that Japan has not done enough to face up to its past.
Japan's relations with some of its neighbours are at their lowest in years, partly because of continued disputes over the war.
Mr Koizumi's apology on Monday was similar to one he made in April, in response to anti-Japanese violence in China sparked by a series of new Japanese school textbooks which played down wartime atrocities.
Doves of peace were released at the controversial Yasukuni shrine
An editorial in Monday's edition of China's state controlled China Daily newspaper made it clear that Beijing still believes Japan has still not adequately faced up to the past.
"Only with an honest attitude towards history can a nation win reconciliation and then integrate into the global community," the China Daily said.
"Actions speak louder than words... [Mr Koizumi's] words appeared faint and his sincerity is also in doubt," the newspaper said, referring to his past apologies.
In other parts of Asia, people voiced their anger against Japan to mark the anniversary.
On Sunday, a group of women in the Philippines demanded compensation for being forced into sex slavery for Japanese troops. Similar protests also take place regularly in South Korea.
Protesters in Hong Kong marched to the Japanese consulate on Monday, chanting that "Japan's hands are full of fresh blood". A similar march took place in Taiwan.
In Tokyo, there was a heavy media presence at the controversial Yasukuni shrine, where Japanese war dead - including 14 class A war criminals - are honoured.
Mr Koizumi's visits to the shrine have triggered anger among Japan's neighbours, but he did not visit the shrine on Monday.
Other senior politicians did visit - including Tokyo Governor Shintaro Ishihara and ruling party executive Shinzo Abe, who is often cited as a candidate to succeed Mr Koizumi.
Other nations are also marking the anniversary of the end of the war with services and memorial events.
In a rare move, a North Korean delegation is in South Korea for the occasion, with senior members of the North's ruling party among the visitors.
In Australia, Prime Minister John Howard paid tribute to his nation's war veterans, who had given the country "the priceless gift of security and freedom".
"Freedom's torch was preserved not just here in Australia, but in the Pacific and in Europe. This was a war of liberation which in a real sense liberated the people of our once bitter enemies," Mr Howard said.