United States President Donald Trump on Sunday said that negotiating with North Korea about its nuclear programme would be a waste of time. Trump’s comments came just hours after US Secretary of State Rex Tillerson said authorities from the country were in direct contact with their North Korean counterparts.

Trump appeared to undercut his top diplomat by declaring on Twitter that any talks would be futile. “Save your energy Rex, we’ll do what has to be done!” Trump had tweeted.

‘Focus on reducing threats’

Tillerson, who is in China, had said on September 30 that the focus was on reducing the threats being exchanged in recent weeks between North Korean leader Kim Jong-un and Trump, after tensions over the Korean peninsula escalated with the North testing several missiles this year.

North Korean state media had on September 3 claimed that they had successfully conducted a hydrogen bomb test. This was the country’s sixth underground nuclear test since 2006.

On September 19, in his first address to the United Nations General Assembly, Trump had called Kim a “rocket man” on a “suicide mission,” prompting Kim to warn the US president that he would “pay dearly” for his comments.