BEIJING // North Korea is expected soon to begin fuelling the rocket that will be launched to mark 100 years since the birth of the country's founder, Kim Il-sung, as satellite images suggest an underground nuclear test will follow shortly afterwards.
The planned launch is widely seen as a test for ballistic-missile technology, sparking international condemnation. Yet it is seen as important for North Korea's fledgling leader, Kim Jong-un, to cement his authority.
Media sources have seen the three Unha-3 rocket components in place on the launch pad, and South Korea's Yonhap news agency yesterday quoted a South Korean official as saying fuelling, taking two to three days, would probably start long before the launch between Thursday and Monday. The centenary of the late Kim Il-sung's birth falls on Sunday.
North Korea has insisted the launch is so that a satellite, used for weather forecasting and surveying natural resources such as forests, can be sent into orbit.
South Korea and Japan have readied military personnel and warned that they will attempt to shoot down parts of the rocket that could land on their territory - action North Korea has warned would spark retaliation.
Although Japan has moved missile interceptors into place, observers said the difficulty of hitting such a rocket means Tokyo is unlikely to take action.
If an unsuccessful attempt was made by Japan "their national integrity would be damaged", said Park Jin-keol from NK Network, a South Korean-based organisation opposed to the Pyongyang regime.
"I don't think any government will try to shoot down the missile. Still [the launch] will cause much tension in the region," he said.
The Sohae rocket launch site in north-west North Korea is being used for the first time, and it is thought debris is less likely to fall on Japan.
The second of the rocket's three booster stages is expected to land in the sea to the west of the Philippines, while reports have said a successful separation of the third stage would represent a major advance in North Korea's intercontinental ballistic missile capability.
Although North Korea has enough fissile material for multiple nuclear weapons, analysts doubt the country can yet mount a nuclear warhead on an effective long-range missile.
Experts have warned there is a risk, albeit small, of the rocket going out of control and landing on South Korea or China.
Satellite images suggest North Korea is simultaneously preparing a site in the north-east for an underground nuclear test, echoing the situation in 2006 and 2009 when rocket launches were followed by subterranean nuclear explosions.
There is evidence of digging at the Punggye-ri centre, where the two previous tests were carried out, and piles of earth that would plug a tunnel before a test, Yonhap reported.
As a result of the planned rocket launch, the United States has cancelled plans to provide food aid to North Korea in return for the scaling back of Pyongyang's nuclear programme and an end to missile tests.
The test however helps the 20-something Mr Kim, who took over as leader on the death in December of his father, Kim Jong-il, to shore up his position among military hardliners.
Mr Kim is likely to take over as general secretary of the Workers' Party of Korea at a conference tomorrow, before the parliament names him chairman of the national defence commission on Friday.
China is North Korea's closest ally and its main food and energy assistance provider. The planned rocket launch and nuclear test indicate the limits to which Beijing is willing or able to exert control over Pyongyang.
"They failed to persuade North Korea to reform, they failed to stop North Korea from testing nuclear weapons before," said Mr Park.
Although a nuclear-armed North Korea is a concern for China, the collapse of the Pyongyang regime would potentially be a bigger problem, generating instability on China's doorstep and possibly a flood of refugees. North Korea in its present form also acts as a buffer from the US-allied South Korea.
"It is in China's interest to maintain the North Korean system, although North Korea gives them a headache," said Park Young-ho, senior fellow at the Korea Institute for National Unification.