WASHINGTON-- Negotiations alone will not rid North Korea of its nuclear ambition, former US ambassador to South Korea Harry Harris argued Tuesday, insisting that US policy of using negotiations to remove North Korea's nuclear weapons is no longer useful.

The former US ambassador stressed the need to combine dialogue with strong sanctions and deterrence to convince North Korean leader Kim Jong-un otherwise.

"The US intelligence community assesses that KJU views nuclear weapons as the ultimate deterrent against foreign intervention," Harris said in a webinar hosted by the Washington Times Foundation think tank, referring to the North Korean leader by his initials.

"KJU declared last year that he would be willing to employ nukes more broadly in wartime, and last September, he stated unequivocally that he would never give up his nukes and the North Korea's status as a nuclear weapons state is irreversible," he added.

Harris, a retired US Navy admiral, also pointed to Kim's remarks at the recently concluded plenary meeting of the North's ruling Workers' Party that Pyongyang will "exponentially" increase the number of its nuclear arsenal.

"That doesn't sound to me like he's going to get rid of his nukes any time soon. In fact, he's telling us precisely the opposite," he insisted.

The former US ambassador to Seoul highlighted the importance of maintaining pressure on the North through deterrence and sanctions.

"We must not relax sanctions or reduce joint military exercises just to get North Korea to come to the negotiating table. This is a fool's error," he said.

"While we hope for diplomacy with North Korea to be successful, we must recognize that hope alone is not a course of action. The quest for dialogue with the North must never be made at the expense of the ability to respond to threats from the North," he added. (Yonhap)