North Korea has invited UN nuclear inspectors to discuss shutting down its Yongbyon nuclear reactor, in the first step towards implementing an international agreement aimed at disarming the communist state.

Pyongyang made the move when it became clear that it would soon receive $25m in previously frozen funds that had been a major obstacle to implementing the nuclear deal reached in February at six-party talks between the US, China, Russia, Japan and the two Koreas.