In the Times interview, Trump explicitly tied his administration's trade policy with China to its perceived co-operation in resolving the North Korea nuclear crisis.
Wu Haitao, China's deputy permanent representative to the United Nations, after a vote on new sanctions against North Korea during a Security Council meeting earlier this month. "If they don't help us with North Korea, then I do what I've always said I want to do".
The sanctions limit energy supplies and ban transfers of any goods to North Korean ships at sea.
But instead of going to Taiwan it transferred the oil to a North Korean ship and three other vessels in global waters on 19 October, South Korean officials were quoted as saying.
The Kaohsiung-based company had leased a freighter for the cargo, and the freighter is believed to have sent oil to vessels bound for North Korea, the statement said.
The newspaper said six other ships that USA authorities say are violating North Korea sanctions are Chinese-owned but registered overseas.
South Korea's customs service concluded that the Lighthouse Winmore had loaded about 12,700 tonnes of Japanese refined petroleum products in South Korea on October 11, reportedly bound for Taiwan, the official said.More news: Justin Timberlake returns with a new single, 'Filthy'
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"The global shipping industry is open, and it is common for ships to change flag country, registration place or charter to other parties", Geng said.
In November, China, one of North Korea's top trading partners, exported no oil products to the isolated country, apparently going above and beyond the United Nations restrictions.
It was not immediately possible to find information for the company.
Taiwan's Presidential Office said the company that chartered the ship was not incorporated in Taiwan, but did not say whether the firm's owner or officials are Taiwanese.
What happened with the Lighthouse Winmore?
The decision came after the UNSC resolution 2397 to tighten sanctions against North Korea in response to its latest ballistic missile launch. China claims that no Chinese oil was exported to North Korea from Beijing in November, a fact meant to illustrate China's willingness to get tough with its unruly client state, although some observers point out that Chinese oil suppliers might also have grown exasperated with North Korea's failure to pay for its oil imports.
This defies a UN Security Council resolution imposed on 11 September.