The United States must develop "rules of the road" with China and other countries to mitigate cyberthreats, Pentagon chief Chuck Hagel said Thursday.

The defense secretary spoke after a Pentagon report found that Chinese hackers have gained access to secret designs for a slew of sophisticated US weapons programs, possibly jeopardizing the American military's technological edge.

Officials say the breaches described in the Defense Science Board paper were part of a broad Chinese campaign of espionage against top US defense contractors and government agencies.

"The United States knows where many of these incursions come from," Hagel told reporters on his plane as he traveled to the annual Shangri-La Dialogue, an international security conference in Singapore.

"It's pretty hard to prove that they are directed by any specific enemy but we can tell where they come from and we've got to be honest about that."

Cybersecurity is set to be discussed for the first time at a meeting of NATO defense ministers next week.

"We've got to find ways, working with the Chinese, working with everybody, (to develop) rules of the road, some international understandings," Hagel said.

The Pentagon chief said Washington would press Beijing using both public diplomacy and private talks.

"I think it's always important when dealing with other nations that you use a very significant range of options," he added.

"I've rarely seen that public engagement resolves the problem but it's important that people understand to state where they are on these issues."

During his stay in Singapore through Monday, Hagel plans to hold multiple bilateral talks with his Asian counterparts.

He pointed to an "evolving" military-to-military relationship with China.

The top US uniformed military officer, Chairman of the Joint Chiefs of Staff General Martin Dempsey visited Beijing in April and Hagel has invited his Chinese counterpart Chang Wanquan to Washington in August.

President Barack Obama is set to meet with new Chinese leader Xi Jingping next week in California.

Australia spy chief says new building safe
Sydney (AFP) May 31, 2013 - Australia's spy chief has declared the nation's new intelligence headquarters secure after reports Chinese hackers stole the building's top secret blueprints.

Speaking for the first time since the reports aired Monday, Australian Security Intelligence Organisation (ASIO) director general David Irvine said security would meet "very, very high standards".

Irvine would not confirm or deny whether Chinese hackers had obtained the floor plan and cable layouts for the security and communications system of the Canberra building.

"We incur all sorts of risks if intelligence operation matters are aired in public," he told a parliamentary hearing late Thursday.

"Can I just assure you though, that I am satisfied that the security of the ASIO building is, and will be, meeting the very, very high standards that are required of a building of that nature."

The Australian Broadcasting Corporation reported on a cyber attack on a contractor linked to the new Canberra headquarters of ASIO which it said was traced to a server in China.

Beijing has said it was "very difficult to find the origin of hacker attacks", with foreign ministry spokesman Hong Lei questioning "where the evidence is for the relevant media to make such reports".

The news came as a Pentagon report also accused Chinese hackers of accessing US weapons designs as part of a large-scale cyber spying campaign against top US defence contractors and government agencies.

China described these as "misjudgements".

In his comments, Irvine said ASIO had also reviewed the terror threat to Australia following the hacking to death of a British soldier in London but concluded it should remain at medium -- a level indicating an attack is feasible and could occur.

"Some sort of crippling fear of a terrorist attack should not dominate the way Australians live their lives," he said.

"Nevertheless we should all... continue to be alert to the fact that there... will be a small number of people within our midst who still talk and some aspire to walk the language of terrorism."

Irvine said the "threat from home-grown lone actor terrorists, or small localised groups who are often largely self-radicalised and see it as some sort of religious or political obligation to conduct an attack" remained.