Preparations for next year's 30th anniversary of normalised Sino-Japanese ties have been forgotten amid a host of disputes over everything from wartime atrocities to tickets for the World Cup. Beijing and Tokyo would like to stage a range of events to mark the occasion but many are under threat as frosty relations refuse to thaw. Professor Gao Heng, of the Beijing-based Chinese Academy of Social Sciences, blamed the problems on China's rising role in world trade. 'It is inevitable that Beijing and Tokyo face some potential conflicts as China's emerging economic role has made Japan feel under pressure,' he said. The oldest and most volatile issues stem from World War II. As a prerequisite before anniversary celebrations can begin, China has demanded an assurance from Japan that Prime Minister Junichiro Koizumi will not visit the controversial Yasukuni War Shrine again, according to Japanese diplomatic sources. Four war criminals are among the 2.5 million Japanese honoured at the shrine. Beijing's request is designed to prevent a repeat of Mr Koizumi's visit to the shrine in August, which sparked protests in China and other countries invaded by Japan during the war. Mr Koizumi was forced to offer a 'heartfelt apology' for war atrocities when he visited China in September. But China's request has received no reply and a positive response from Tokyo is unlikely, the sources say. China has also expressed concerns over Japanese history text books. Beijing and other Asian countries accuse the book's authors of 'glorifying wartime atrocities'. Taiwan has also cast a shadow on the anniversary. Beijing has always been sceptical of Tokyo's stance on Taiwan, despite Japan's support for the 'one China' policy, which means Tokyo only has official relations with the mainland. In April, a diplomatic stand-off emerged when Japan granted a visa to former Taiwan president Lee Teng-hui, an old foe of the mainland, so he could have a medical examination. National People's Congress Chairman Li Peng postponed a trip to Japan in apparent retaliation for Mr Lee's visa. Beijing, which has not ruled out the use of violence if Taiwan declares independence, worries Japan will meddle in the Taiwan Strait. The Chinese military is aware that Japan is considering buying three or more transport planes, each capable of carrying 200 people and flying 10,000km. What the mainland finds most disturbing is that the aircraft could reach the Taiwan Strait without refuelling. Beijing's concerns grew on July 6 when Japan's Parliament passed the 2001 Defence White Paper that cited China's potential military threat as one of the reasons for Japan's military expansion. The document immediately triggered an outcry from the mainland military, which accused Japan of exaggerating the threat from China. While the right-wing in Japan has urged Tokyo not to submit to Beijing's warnings to stay out of Taiwan, China has refused to support Japan's bid to become a permanent member of the United Nations Security Council. But the challenges to Sino-Japanese relations are not confined to military or diplomatic fronts. Economic issues also pose huge difficulties. Days before the year ends, Sino-Japanese ministerial talks have avoided an all-out trade war by settling a trade dispute. The details have yet to be worked out. Beijing and Tokyo had vowed to impose punitive measures on each other to stop unfair trade. Next summer's football World Cup - jointly hosted by Japan and South Korea - may lack the gravitas of international trade and diplomacy, but the event most effectively sums up the widespread tensions in Sino-Japanese ties. The Chinese team has reached the finals for the first time. But its fans might not have enough tickets. According to diplomatic sources, both sides have started negotiations to prevent the sporting event being spoiled by politics. Despite the clouds shadowing relations, analysts say there is still reason for hope. Thanks to the anti-terrorist campaign, for instance, Beijing and Tokyo have joined hands to protect themselves from terrorist attacks. 'There are some conflicts, but I believe that both sides can handle them,' Professor Gao said. 'But that will require wisdom from leaders on both sides.'