China is key in N Korea nuclear crisis, says Pentagon chief

US Defence Secretary Ashton Carter today called for further pressure on North Korea after the renegade state carried out a new nuclear test, but said China bore "responsibility" for tackling the problem.
"We need to... Redouble the pressure on North Korea," Carter told reporters on a visit to Oslo.
He pointed to moves to strengthen defences in the region, including the deployment of advanced anti-missile systems.
"One of the things I'd like to single out is the role of China," Carter said, referring to North Korea's main ally.
"China shares important responsibility for this development and has an important responsibility to reverse it," he said.

"It's important that it use its location, its history and its influence to further the denuclearisation of the Korean peninsula and not the direction things have been going."

The underground test, the fifth and most powerful in North Korea's controversial nuclear programme, was announced by state media in Pyongyang earlier Friday.
The explosion had a yield of 10,000 kilotonnes, according to experts.
The UN Security Council was to meet later Friday to discuss a response.
North Korea has been hit by five sets of UN sanctions since it first tested a nuclear device in 2006.