References to the Yasukuni war shrine were conspicuous by their absence during Premier Wen Jiabao's appearances in Japan this week - testimony to the nuance and verve of his diplomacy. Mr Wen avoided Yasukuni during his historic address to the Japanese parliament, the Diet, on Thursday and did not demand further war apologies - Japanese officials said he did not mention Yasukuni in private talks either. While still describing the 'deep scars' in the hearts of Chinese people after Japanese invasions, he reverted to a more moderate formula from friendlier times - that both ordinary Japanese and Chinese people had suffered in the 20th century's wars. The result? He has now made it much harder for his Japanese counterpart, Shinzo Abe, to risk a return to the deep freeze by visiting the shrine, where 14 class-A war criminals executed at the end of the second world war are enshrined along with 2.5 million Japanese war dead. Mr Abe, a conservative blue-blood related to war-era leaders, had been an enthusiastic visitor before taking office. Later this year he might have been tempted to visit again during August or for autumn rites, particularly if he faces internal party political pressures after July Upper House elections. Japanese officials yesterday said he had still not confirmed if he would visit as prime minister. Mr Wen's diplomacy has made the question increasingly academic as both sides prepare broadening ties across a range of fronts - economic, military, environmental and diplomatic. 'Nothing has been ruled out but it is fair to say that it is very hard to imagine a visit to the shrine by Mr Abe in the current climate,' said one Japanese official privately. Now the hard work begins. Putting flesh on the bones of developments could prove difficult in the months ahead. The decision to start military exchanges remains largely symbolic and should be relatively straightforward. Actual progress to ease tensions across the disputed sea border across the East China Sea is a tougher test. Working-level meetings are due to restart next month and will be closely watched for progress towards meaningful future joint exploitation and co-operation. The proposed high-level economic co-operation is certainly ambitious. A firm agenda has not yet been set but Japanese Foreign Minister Taro Aso is eyeing a body to cover 'horizon' issues that do not fit easily into ministry-to-ministry talks, including global environmental and trade issues, and international co-operation. Japanese Foreign Ministry spokesman Noriyuki Shikata acknowledged there was a great deal of hard work ahead. 'We wouldn't say that some of these issues will be easy to resolve,' he said. '[But] there is a good foundation to build on.' As backroom talks continue, one key sign of further warmth will be a return visit to Beijing by Mr Abe later in the year. Such a move is expected to lead to a visit to Tokyo by President Hu Jintao . As the diplomats pat themselves on the back for turning the relationship around in less than a year, changing political cultures could prove more tricky. Young mainlanders still express fierce anti-Japanese sentiments, while ultra-nationalists still patrol the streets of Tokyo with loud speakers, wallowing in an imperialist past. Their black vans, often seen around the Yasukuni Shrine, have been particularly active this week.