A controversial flag became the latest sticking point in an intensifying dispute between South Korea and Japan on Wednesday as Seoul asked the International Olympic Committee to ban its use at the Tokyo Games next year.

The 'Rising Sun' flag has been an ensign for Japan's Maritime Self-Defence Forces since 1954, but in much of East Asia, it is seen as a symbol of the country's military aggression during World War II. But last week, Tokyo's Games organisers dismissed the claims that the emblem is a political statement and said they will allow the flag at the Olympics.

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Clear political symbol: Seoul Sports Ministry

That caused an uproar in South Korea, prompting it to lodge a formal complaint to the IOC. World football's governing body FIFA has already banned the flag's use. "We explained the history behind the flag and demanded it be banned during the Olympics," Seoul's sports ministry said in a statement. The flag was a "clear political symbol" that stirs up painful memories of Japan's wartime atrocities, the ministry added, likening it to the "nightmares that the Nazi's Swastika gives to Europeans".

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Koreans remain deeply resentful of Japan's 1910-45 colonisation of the peninsula and the neighbours -- both of them US allies -- are embroiled in a long-running dispute over wartime history.

A trade war between Japan and South Korea 

The row spiralled into a bitter trade war in recent months after a series of South Korean court rulings ordering Japanese firms to pay for forced labour during Tokyo's colonisation. The feud has seen Japan impose new restrictions on exports crucial to South Korean tech giants in July and led to the neighbours removing each other from their lists of trusted trade partners. South Koreans have since mounted a widespread boycott of Japanese goods, which saw a plunge in sales of Japanese cars and forced several airlines to suspend routes to their neighbour because of falling demand.

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Some lawmakers have pushed for a boycott of the Tokyo Olympics and a travel ban on the country, citing supposed radiation risks from the Fukushima disaster eight years ago. The South's Olympic committee said last month it lodged a complaint to the Tokyo Games organisers over radiation risks at venues around Fukushima as well as the possibility of food produce grown in the region being served to athletes in the Olympic village. 

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