US military aircraft defies China's new defence zone to fly over disputed East China Sea "The policy announced by the Chinese over the weekend is unnecessarily inflammatory," said the White House spokesman Josh Earnest. These are the kinds of differences that should not be addressed with threats or inflammatory language, but rather can and should be resolved diplomatically. China's approach to the disputed islands has been increasingly bellicose since Xi Jinping, the new president of China, took office in March. Regional analysts said declaration of the zone was seen partly as a move by Mr Xi to build his leadership credentials with a domestic audience, but also as part of desire to test the resolve of the US and its regional allies. Officially the US is neutral about the disputed island chain, however the US would defend them under its commitments in Article 5 of the US-Japan Security Treaty, said Nicholas Szechenyi, a senior fellow at the Centre for Strategic and International Studies. The US has stated repeatedly that any attempt to change the status quo unilaterally or through coercive means would be unacceptable. The B-52 flights were intended to reflect that," he said. The bombers flew out of the US territory of Guam on Monday. US officials insisted the flights were long-planned and not in direct reaction to China's latest declaration. The Chinese announcement of the zone was immediately disputed at the weekend by South Korea as well as Japan which summoned Chinese diplomats to protest. Tokyo ordered two of its biggest airlines, ANA and Japan Airlines, to stop filing flight plans with the Chinese as a demonstration of Japan's disapproval. China did not respond publicly to the US flights, however the Chinese defence ministry said it had lodged protests with the US and Japanese embassies in Beijing over the criticism from Washington and Tokyo of the zone. In a move likely to raise concerns about Chinese aggression, Beijing sent its sole aircraft carrier for its first training mission into the South China Sea on Tuesday, amid maritime disputes with the Philippines and other neighbours. The dispute between China and Japan over the Senkakus, which sit atop potentially vast oil and gas reserves, has simmered for decades, but heated up in September 2012 when Japan nationalised three of the islands. The move provoked fury in Beijing and a series of cat and mouse games between Chinese and Japanese ships and aircraft that analysts warned carried the serious risk of sparking an accidental conflagration. China's unilaterally declared zone overlaps with a Japanese zone that was declared in the 1960s and over which the Japanese keeps records of foreign incursions - a practice which China was expected to mirror as part of its desire to get the islands internationally recognized as "disputed." "The Chinese zone is part of a long-term Chinese strategy to assert sovereignty in maritime domain and airspace and I think we can expect to see a lot more of this as time goes by," added Mr Szechenyi. The B-52 flights were a rare display of intent by the US, which used a similar tactic over the Korean peninsula last March, when it flew a pair of the bombers over South Korea territory as a signal to the North not to overstep its mark. Using a similar tactic against China has potentially far great consequences, drawing reminders of the far more serious Taiwan Straits crisis of March 1996. China has since invested heavily in an anti-ship ballistic missile programme that would make such a deployment massively more risky in the future and is reportedly already changing US strategic calculations in the region.