How close has North Korea come to producing a nuclear device if not a finished weapon? Much closer than its technology allowed in 1994 when the first crisis erupted, according to US and South Korean intelligence estimates.
The escalating tension over the North's refusal to open up its suspect facilities for international inspection at that time nearly triggered a US air strike ordered by then-US president Bill Clinton.
A last-minute intervention by former president Jimmy Carter helped clear the way for a compromise in the form of the Agreed Framework signed in Geneva in October 1994 between the US and North Korea.
Pyongyang agreed to freeze its nuclear activities in exchange for a safer nuclear electric power-generating facility to be provided by an international consortium - the Korean Peninsula Energy Development Organisation - headed by the US and South Korea.
Initial suspicions over the North's intentions arose a dozen years ago when the International Atomic Energy Agency (IAEA) conducted its first on-site inspection of nuclear facilities in Yongbyon, not far from Pyongyang.
It followed the North reporting that it had 90 grams of reprocessed plutonium in its possession. IAEA officials promptly demanded access to two facilities storing nuclear waste material. When the North opened just one facility for IAEA inspection, suspicions rose.
A year later, in March 1993, when the nuclear watchdog demanded a special, challenge inspection, Pyongyang stunned the world by unilaterally withdrawing from the nuclear non-proliferation treaty regime.