Analysts believe the latest test, the biggest yet, “hurt China’s national interests and damaged regional stability”.
The detonation which came shortly after two successive missile tests, provoked international outrage.
Wang Sheng, of Jilin University, told the South China Morning Post that Beijing might consider tougher restrictions on trade with Pyongyang, including reducing oil exports, because it was “seemingly the only way to show pressure at this moment,”
Donald Trump‘s US administration was pushing China to take the step, according to The New York Times reported, adding that senior US officials described it as a last best chance to resolve the crisis by non-military means.
China, North Korea’s sole major ally, accounts for about 90 per cent of its international trade and most of its imported energy supply. Beijing sends some 500,000 tonnes of crude oil and 270,000 tonnes of refined products over the border each year, according to United Nations (UN) figures.
But Jia Qingguo, of Peking University, told the South China Morning Post that China would not cut off its neighbour completely to avoid the collapse of the Kim regime and a potential influx of refugees.
Asked at a briefing whether Beijing would consider reducing oil shipments, a Chinese foreign ministry spokesman said his country “will promote denuclearisation and the maintenance of stability on the peninsula, and promote solving problems on the peninsula through dialogue and consultation.”
Vladimir Putin said that imposing tougher sanctions on North Korea over its nuclear missile programme would be counter-productive and said threats of military action could trigger “a global catastrophe”.
Speaking after a BRICs summit in China, the Russian President criticised US diplomacy in the crisis and renewed his call for talks, saying Pyongyang would not halt its missile testing programme until it felt secure.
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“Russia condemns North Korea’s exercises, we consider that they are a provocation … [But] ramping up military hysteria will lead to nothing good. It could lead to a global catastrophe,” he said.
Russia exports about 40,000 tonnes of oil and related products to North Korea per quarter, Mr Putin said, calling the quantity “negligible”.
Germany’s leader Angela Merkel, however, said new sanctions were “required urgently”.
Additional reporting by agencies