TRACY BOWDEN, PRESENTER: The threats and counter threats continue in the Korean Peninsula, after what the US has called the latest round of bellicose rhetoric from North Korea.

North Korean leader Kim Jong-un has declared a state of war and threatened to increase his country's nuclear capability. South Korea and the U.S. have warned of military retaliation.

So how real is the risk of a nuclear confrontation?

A short while ago I spoke to Professor Andrei Lankov from Kookmin University in Seoul. A native of the former Soviet Union, Professor Lankov lived as an exchange student in North Korea in the 1980's and is seen as one of the world's leading experts.

TRACY BOWDEN: Andrei Lankov, how seriously should these threats from North Korea be taken?

ANDREI LANKOV, KOOKMIN UNIVERSITY, SEOUL: Frankly, not too seriously and I would say that it probably be better if the world paid no attention whatsoever to all these threats. North Koreans are not going to attack. And they have seen very similar, not exactly the same, but very similar developments, many, many times before.

TRACY BOWDEN: In your view, what's prompted this latest round of what the Americans are calling bellicose rhetoric?

ANDREI LANKOV: First of all, an international reaction to the third nuclear test and the successful long-range missile launch - plus exercises. However, once again, there is nothing particularly special about it. Back in 2009, when North Korea had its previous nuclear test, they saw a very similar reaction. The difference is that this time, the reaction is, I would say, much louder than usual. But the basic content is the same.

TRACY BOWDEN: Is any of this to do with Kim Jong-un trying to solidify his position as the new leader?

ANDREI LANKOV: Well, really nobody knows. I would say that there are two possible explanations why this time North Koreans are reacting stronger than usual. First, as you have mentioned it's quite likely he wants to show to his own military and to his own people that he is a very tough and serious leader. In spite of all his boyish looks - he's probably not even 30 yet, and seriously overweight by the North Korean standards. He just want to show that, "Well, I might look fat and young, but I am a brave general ready to fight the American imperialism." And also wants to distract his people from the economic problems with domestic economy.

But there is another explanation as well. For many years, actually for decades, North Korea has played the same trick, which until recently has worked well. First, they manufacture a crisis. They behave pretty much like they're behaving now. They drive tensions high. And sooner or later, the international community and the major players begin to feel unwell and tense and insecure. At that point, North Koreans suggest to start negotiations, and they extract aid and other concessions in exchange for their willingness to return to the status quo. So, they first manufacture a crisis, and then they get paid for resolving the crisis. This approach, these tactics have worked perfectly well for many, many years, but recently it's losing its efficiency, because the outside world, above all the United States, have finally learned how it usually works with North Korea and they are not really rushing with money and concessions. And this is what North Korea wants above all: money and concessions from the outside world. So, obviously, it's quite possible that the North Korean decision makers decided to go really seriously loud this time.

TRACY BOWDEN: South Korea and the US though have warned of a strong military response to provocation. Is there a chance this could escalate?

ANDREI LANKOV: Well, first of all, there is very little chance of provocation. The experience has shown us when North Koreans are threatening this attack, they never attack. When they attack, they attack suddenly without any warning. So, basically, I don't expect any provocation. Of course some unlucky incidents might happen, and in this regard, yes, we face a threat of escalation largely because in the past the South Korean and American military, they usually were very soft on North Korea, even when the North Koreans started some kinds of shoot-outs, of military clashes on their DMZ or NLL, that is essentially land and sea border between two Koreas. Now, the common assumption is that this time the South Korean and American forces will strike back and this might be dangerous because the North Korean side might decide that their reaction was excessive, and indeed, we'll face a risk of escalation. However, once again, right now, the probability of a North Korean attack does not appear high. When North Koreans want to attack, they just attack, they don't warn.

TRACY BOWDEN: Is there in any danger that Kim Jong-un has talked the talk and ultimately may have to walk to walk?

ANDREI LANKOV: Why? Is he stupid? Is he suicidal? Is he zealot? Does he believe in any ideology? Does he want to destroy the world in the name of God or whoever? Of course not. He loves his life. He loves his wife. He loves his cars and his toys. He's not going to start a war; he has no chances to win.

TRACY BOWDEN: Andrei Lankov, thank you very much for speaking to us.

ANDREI LANKOV: Thank you.