"North Korea is following a simple strategy. They want to show the world they have nuclear weapons to prevent any sanctions or strikes by the US," said Eberhard Sandschneider, head of the influential German Council on Foreign Relations (DGAP).
Slapping sanctions on North Korea after its nuclear test would be unlikely to have any major impact, insisted Sandschneider in an interview with Deutsche Presse-Agentur (DPA).
"Sanctions work badly and this regime has shown it is highly resistant to sanctions," he said. "They would probably only strengthen the North Korean regime."
Other forms of pressure were also unlikely to bring any positive results unless they were backed by military threats, said Sandschneider, adding: "But this would lead to catastrophe."
The only possible option for dealing with North Korea - as well as with Iran over its nuclear programme - remained "credible talks without any preconditions," he said.
"Security is what is of vital importance to the North Korean regime," said Sandschneider.
Any such talks would have to be initiated by the US which North Korea views as its major threat, he said, adding that North Korea had "no fear of Japan or South Korea."
Asked whether there was now a danger that North Korea's nuclear test could push non-nuclear Asian countries such as Japan and Taiwan to build nuclear weapons, Sandschneider said: "This is the danger."
He warned that the international community now had "a lot of work ahead" to prevent nuclear proliferation in Asia similar to that between India and Pakistan which both tested nuclear weapons in 1998. "There are parallels here. One state arms and the others try to follow," said Sandschneider.
North Korea's official Korean Central News Agency (KCNA) said the country had followed through on its threats and successfully conducted an underground nuclear test on Monday.
(DPA)
