Glyn Davies, the US special envoy on North Korea policy, was speaking to reporters in South Korea's capital Seoul when he said:
Whether North Korea tests or not, it's up to North Korea. We hope they don't do it, we call on them not to do it. It will be a mistake and a missed opportunity if they were to do it.
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After Roy Hodgson's resignation following England's humiliating exit from Euro 2016, who are the leading contenders to replace him?
The beleaguered Labour Party leader is clinging onto power in the face of as many as 150 MPs voting to remove him from the top job today.
Mr Osborne said he is "not the person to provide the unity my party needs".