US wants hacker attacks resolved amicably CYBERATTACKS originating in China are becoming a serious military concern that need to be addressed urgently and amicably, US Defence Secretary Chuck Hagel says. China has been behind a long string of cyberattacks, cyber-espionage, sabotage and hacking attacks, charged Hagel, speaking at the 12th Shangri-La Dialogue defence conference in Singapore on Saturday. He said the Obama administration was committed to working with China and would take all necessary steps to defuse the situation. The Pentagon chief called for closer international dialogue on cyber attacks and greater cooperation in setting up rules to mitigate future conflicts. "We are determined to work more vigorously with China and other partners to establish international norms of responsible behaviour in cyberspace," said Hagel. The setting up of a common cyber working group which protects mutual interests and builds bilateral trust is the first positive step in fostering US-China dialogue on cyberwarfare. Hagel's remarks come at a time when US intelligence chiefs have ranked cyberattacks above terrorism as America's main national security threat. In March, on his maiden visit to Beijing, US Treasury Secretary Jack Lew also urged newly installed Chinese President Xi Jinping to put a stop to cyberattacks aimed at American state agencies and departments. President Barack Obama is also known to have raised his concerns about computer hacking in a telephone conversation with Xi at about the same time. During his speech, Hagel also affirmed the strengthening of the US pivot towards Asia, a move that would entail a major deployment of American troops to the Asia Pacific region from the Middle East and Europe by 2020, as a part of rebalancing US interests in the region. "We will keep strengthening our presence in Asia despite major budget cuts at home," said Hagel. He also announced the Obama administration had set aside $US100 million ($A104 million) to expand its military exercises in the region.