Trump Says He Knows What's Going On With Kim Jong-Un But 'Can't Tell'

US President Donald Trump has fuelled further speculation over North Korean dictator Kim Jong-un's health, claiming he has "a very good idea" of the leader's condition but cannot "talk about it".

Speaking at a White House briefing on Tuesday, Trump teased reporters they'd "probably be hearing about" Kim's wherabouts "in the not-too-distant future".

He declined to comment further but said he wished Kim well.

"I have a very good relationship. If I wasn’t President you would have been at war with North Korea – he expected that, I can tell you,” the president added.

Trump had previously said he did not believe a CNN report that Kim was gravely ill after undergoing surgery, adding it had been based off "old documents".

It comes as a South Korean foreign policy adviser attempted to silence rumours about Kim's health on Monday, claiming he is "alive and well".

President Moon Jae-in’s foreign policy adviser told Fox News Kim is staying at his holiday palace on the North Korean coast.

“Our government position is firm.....Kim Jong-un is alive and well, “ Chung-in Moon said on Sunday.

“He has been staying in the Wonsan area since April 13. No suspicious movements have so far been detected.”

Unification Minister Kim Yeon-chul also said South Korea has “enough intelligence to confidently say that there are no unusual developments” at a forum in Seoul on Monday, according to AP.

Last Thursday, China sent a team of medical experts to North Korea to monitor the 36-year-old's health.

Satellite images of the Kim's train showed it was parked in Wonsan last week, adding weight to the claims the leader had been recovering from surgery.

The North Korean leader has not been seen publicly since April 11.

Concerns were raised about Kim's whereabouts after he missed his grandfather's birthday celebrations on April 15.

Despite the leader missing from the public eye, North Korean media has continued to publish Kim's 'comments'.

In one report, Kim was quoted expressing his appreciation for workers who have toiled on a series of construction projects throughout the nation.

The hermit nation is notoriously secretive, and gathering intelligence about its leaders is no easy task.

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