【明報專訊】Nuclear technology is a double-edged sword. To prevent it from being used destructively, the US and North Korea signed the US-DPRK Agreed Framework (《朝美核框架協議》) on 21 October 1994 in Geneva, Switzerland.

1. Nuclear Non-proliferation Treaty

The Nuclear Non-proliferation Treaty (NNPT,《核不擴散條約》) was opened for signature in 1968 in London, Moscow and Washington. By 5 March 1970, when the treaty was closed for signature and came into effect, there were nearly 100 signatories. It was open to countries that did not sign the NNPT (like China and France) to accede to it. The NNPT now has more than 180 member states and its validity has been extended indefinitely.

The NNPT lists five countries — China, France, Soviet Union (now Russia), the UK and the US — as nuclear weapon states (NWS), and the rest as non-nuclear weapon states (NNWS). The NWSs agree that they will never "transfer nuclear weapons or other nuclear explosive devices to" or "in any way to assist, encourage or induce" NNWSs to acquire nuclear weapons. The NWSs would eventually disarm themselves of nuclear weapons. However, the use of nuclear energy for non-military purposes is allowed.

2. Nuclear programme of North Korea

North Korea developed its nuclear technology for electricity generation in the 1950s and 1960s. The country acceded to the NNPT in December 1985. It rapidly built several high-output reactors within a decade, but the output was believed greatly to exceed the demand for generating electricity.

There were international suspicions that North Korea was making nuclear weapons.

At the same time the US assisted South Korea to construct its own reactors, and North Korea found the move threatening. The International Atomic Energy Agency (IAEA, 國際原子能機構) inspected North Korea six times in 1992 and 1993, but inspection requests made in 1993 were denied. North Korea then declared that it would withdraw from the NNPT, although the declaration didn't come into effect.

3. The framework and the six-party talks

The US sought to reach an agreement with North Korea. The two countries signed the US-DPRK Agreed Framework on 21 October 1994. North Korea agreed to halt the operation and infrastructure development of its nuclear programme and, in return, the US offered it a package of economic and diplomatic benefits.

The framework requires North Korea to dismantle(拆卸) its gas-graphite reactor, which can be used to produce nuclear weapons and allow the IAEA to inspect its facilities. North Korea promised not to withdraw from the NNPT. On the other hand, North Korea would be provided with large quantities of oil so that it could meet its energy demand. It was agreed that the two sides would make the Korean peninsula nuclear-free.

However, in 2002, North Korea said it had planned to restart Yongbyon reactor. The US stopped providing it with oil. Thereupon, North Korea withdrew from the NNTP and re-launched its nuclear programme. In 2003, the two countries, together with South Korea, China, Japan and Russia, had the first six-party talks (六方會談). The objective is to resolve the North Korea nuclear issue diplomatically.

4. Period of uncertainty

At the six-party talks some results were achieved. However, North Korea launched two nuclear tests in 2006 and 2009 and refused to take part in any six-party talks in 2009. In 2013, it had another nuclear test.

In July 2014, Chinese President Xi Jinping (習近平) visited South Korea and met with President Park Geun-hye (朴槿惠). A joint declaration was released condemning North Korea for developing nuclear weapons. The declaration also mentioned the possibility of restarting six-party talks.