Evgeny Kim, from the Russian Academy of Sciences, says tackling North Korea's nuclear programme has always depended upon its relationship with the US.

“The North Korean problem is between the US and North Korea and we are all held hostage to that relationship. For the past maybe nine years the North Koreans have been saying: establish a diplomatic and stable relationship with us, let’s sign a non-aggression treaty between the US and North Korea, and we won’t have any nuclear weapons. We have always wanted to have bilateral talks with the US,” Evgeny Kim explained.

In April, North Korea withdrew from talks involving Russia, China, South Korea, the US and Japan.

The move followed international condemnation of North Korea’s missile tests.

Aleksandr Vorontsov from the Institute of Oriental Studies in Moscow says North Korea has said many times that they will answer negotiations with negotiations and pressure with super-pressure – that’s their usual tactics.

“The most important thing is that this is the first time that North Korea has said it is ready to return to the six-party talks, because before they have repeated that the six-party talks are dead and they will never come back,” Vorontsov says.

And thus the reports that North Korea is preparing to restart a nuclear reactor at Yongbyon may be connected with their wish to demonstrate that they are independent and can answer pressure, he added, as their opponents in the six-party talks previously said that even if the nuclear-related talks would start, the sanctions against North Korea should be implemented in full.