Secretary of State John Kerry, speaking exclusively to ABC's Martha Raddatz for "This Week," compared the reported arrest and execution of the uncle of North Korean dictator Kim Jong Un to the actions taken by former Iraqi dictator Saddam Hussein and said they were an "ominous sign of the instability" in North Korea.

"It really reminded me of a video that we saw of Saddam Hussein doing the same thing, having people plucked out of an audience, and people sitting there sweating, and nobody daring to move or do anything," Kerry said during an interview in Vietnam yesterday.

Kerry told Raddatz that the actions taken by the mysterious young leader of the secretive regime show his true nature.

"It tells us a lot about, first of all, how ruthless and reckless he is. And it also tells us a lot about how insecure he is, to a certain degree," he said.

READ a Full Transcript of Martha Raddatz's Interview With Secretary John Kerry.

"It tells us a significant amount about the instability, internally, of the regime, with the numbers of executions. This is not the first execution. There have been a significant number of executions taking place over the last months which we're aware of," Kerry added.

"North Korea remains relatively opaque. It is not easy. But we do have insights. And the insights that we have tell us that he is a spontaneous, erratic, still worried about his place in the power structure and maneuvering to eliminate any potential kind of adversary or competitor, and does so, obviously, ruthlessly," Kerry said later in the conversation with Raddatz.

KCNA/Reuters

The secretary of state told ABC News the execution also highlights the importance of continuing the effort to stabilize the region.

WATCH Kerry on "This Week" in 1984.

"It underscores the importance for all of us of finding a way forward with North Korea in order to denuclearize the peninsula. We've made progress with China. China is critical to any successful outcome with respect to denuclearizing North Korea. And we are now doing a more cooperative approach to the peninsula," Kerry said .
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MARTHA RADDATZ, HOST: Mr. Secretary, I want to get right to reports out of North Korea that the young leader, Kim Jong Un, has executed his uncle, his mentor, one of the most powerful people in North Korea.

What does this tell you about the danger coming from North Korea?

JOHN KERRY, SECRETARY OF STATE: Well, it tells us a lot about, first of all, how ruthless and reckless he is. And it also tells us a lot about how insecure he is, to a certain degree.

It tells us a significant amount about the instability, internally, of the regime, with the numbers of executions. This is not the first execution. There have been a significant number of executions taking place over the last months which we're aware of.

And most importantly, it underscores the importance for all of us of, uh, finding a way forward with North Korea in order to denuclearize the peninsula. We've made progress with China. China is critical to any successful outcome with respect to denuclearizing North Korea. And we are now doing a more cooperative approach to, uh, to the peninsula.

But it's a - it's very - it's an ominous sign of the instability and of the danger that does exist.

RADDATZ: What - what does it tell you about him?

We know so little about him.

Do we know any more about him?

KERRY: Well, we don't know. I mean North Korea remains relatively opaque. It is not easy. But we do have insights. And the insights that we have tell us that he is a, you know, spontaneous, erratic, uh, still worried about his place in the power structure and maneuvering to eliminate any potential kind of adversary or competitor and does so, obviously, ruthlessly.

I mean you - you saw the pictures of his uncle being arrested in front of everybody at this…

RADDATZ: And this was so public.

KERRY: - meeting. I mean it really reminded me of - of a video that we saw of Saddam Hussein doing the same thing, having people plucked out of an audience and people sitting there sweating and nobody daring to move or do anything.

Um, this is the nature of this ruthless, horrendous dictatorship and of his insecurities. And - and I think we - we need to factor that into the urgency of getting China, Russia, Japan, South Korea, all of us, uh, to stay on the same page and to put as much effort into the denuclearization as possible. To have a nuclear weapon, potentially, in the hands of somebody like Kim Jong In - Jun - just becomes even more unacceptable.

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