US Secretary of State Rex Tillerson said Sunday that President Donald Trump wants him to continue his diplomatic efforts to resolve the growing tensions over North Korea's burgeoning nuclear weapons program.

And America's top diplomat said, "those efforts will continue until the first bomb drops."

In an interview with CNN, Tillerson tried to minimize tweets the president recently sent that appeared to undermine the secretary of state's diplomatic efforts and credibility. In response, Tillerson reportedly called Trump a "moron," an accusation he has denied.

At the beginning of the month Trump took to Twitter, saying that Tillerson was wasting his time trying to negotiate with North Korea's leader Kim Jong Un, whom Trump referred to as "Little Rocket Man."

Trump "has made it clear to me to continue my diplomatic efforts," Tillerson said.

The secretary of state's comments come amid rising tensions with the North over a series of nuclear bomb tests conducted in recent weeks by the repressive regime. A pair of North Korean missile tests also rattled the US and its allies, particularly South Korea and Japan.

Castrating US diplomacy?

Tillerson has been negotiating with China in an attempt to get the Asian giant to press North Korea to back down.

Trump's tweets were widely seen as undercutting his government's diplomatic efforts. Senate Foreign Relations Committee Chairman Bob Corker, a Republican, publicly rebuked the president for "castrating" his the secretary of state and undermining his diplomatic efforts.

But Tillerson sought to minimize the controversial tweets on Sunday, saying that was Trump's way of trying to move the ball forward.

He added that Trump has a very good relationship with Chinese leader Xi Jinping.

"Rest assured that the Chinese are not confused in any way what the American policy [is] towards North Korea or what our actions and efforts are directed at," he added.

The US has long wanted the Pyongyang to abandon its nuclear program, a prospect that seems virtually unimaginable today.

bik/sms (Reuters, AP)