The U.S. ambassador to China says the U.S. would be ready to talk with North Korea if the North renounces further nuclear and missile tests and follows through on that pledge.
Ambassador Terry Branstad told Bloomberg Television on Wednesday that if North Korea announces that it will not conduct any more nuclear tests or launch any more missiles, he believes there’s an opportunity for the U.S. to get back to the negotiating table.
He made the comment after being asked about what it would take for talks to start with Pyongyang.
Speaking on the sidelines of the Fortune Global Forum in Guangzhou, China, the former Iowa governor also said that sanctions against North Korea were “starting to have an impact.” 
He called North Korean leader Kim Jong-un’s push for nuclear weapons “the biggest threat to humankind right now.”  
He then repeated the Trump administration’s call for China to cut off oil sales to Kim's regime.
He said that sanctions need to go further, and labor by North Koreans in China and other countries also "needs to stop."