North Korea announced Saturday it will launch a rocket later this month, triggering condemnation from the US and racking up tensions with South Korea which is just days from a presidential election.
It will be the North's second long-range rocket launch this year following a much-hyped but failed attempt in April.
In a statement carried by the Korean Central News Agency (KCNA), the Korean Committee for Space Technology said the new bid would be carried out between December 10 and 22.
The United States and South Korea urged Pyongyang to scrap the launch, while Tokyo reportedly postponed talks due next week with North Korea and ordered its military to prepare to shoot down the rocket if it goes over Japan.
Washington warned that the "highly provocative" plan would destabilise the region.
"Devoting scarce resources to the development of nuclear weapons and long-range missiles will only further isolate and impoverish North Korea," State Department spokeswoman Victoria Nuland said in a statement.
The South Korean foreign ministry said the planned launch was a "deeply provocative act" that defied UN resolutions and would have significant repercussions for the already isolated state.
Japanese Prime Minister Yoshihiko Noda announced the postponement of the talks scheduled for Wednesday and Thursday in Beijing, Kyodo news agency said, which were due after a meeting last month between the countries' diplomats in Mongolia.
Japanese Defense Minister Satoshi Morimoto ordered the military to prepare to shoot down the rocket if it, or part of its debris, looked likely to come down on Japanese territory, Jiji Press reported.
As in April, the North said it would be a purely "peaceful, scientific" mission aimed at placing a polar-orbiting earth observation satellite into orbit.
The US and its allies insist the launches are disguised tests for an inter-continental ballistic missile (ICBM) capable of carrying a nuclear warhead.
As such they would contravene UN resolutions triggered by Pyongyang's two nuclear tests in 2006 and 2009.
They say the North's Unha-3 rocket is actually a three-stage variant of the Taepodong-2 ICBM that Pyongyang has been developing for years but has never tested successfully.
Saturday's announcement ended weeks of intense speculation, based on satellite image analysis, that the North was preparing a fresh launch from its Sohae satellite launch station.
South Korea had repeatedly warned in recent months that the North would seek to destabilise the situation on the Korean peninsula ahead of the South's presidential election on December 19.
"We sternly warn if the North goes ahead with the launch, it will face strong countermeasures from the international community," Saturday's foreign ministry statement said.
British Foreign Secretary William Hague also called on Pyongyang to call off the launch, warning it would "damage the prospects for peace and stability on the Korean Peninsula".
On Thursday the UN Security Council had warned Pyongyang that going ahead with another launch would be "extremely inadvisable".
Professor Yang Moo-Jin of the University of North Korean Studies in Seoul suggested it was timed to coincide with the first anniversary of North Korean leader Kim Jong-Un assuming power following the death of his father Kim Jong-Il on December 17.
"It plans to launch the rocket as a kind of celebratory firework," Yang said.
"North Korea lost face when it failed with the April attempt and Kim Jong-Un thinks amends need to be made," he added.
The North's statement said scientists had analysed April's failure - when the rocket exploded after take-off - "and deepened the work of improving the reliability and precision of the satellite and carrier rocket".
The April launch put a halt to the latest international effort to engage North Korea, with the United States calling off plans to deliver badly needed food assistance.
The KCNA statement said the December mission would "fully comply" with relevant international regulations governing satellite launches.
"A safe flight path has been chosen so that parts of the carrier rocket that might fall during the launch process would not affect neighbouring countries," it said.
The announcement came just days after South Korea had been scheduled to carry out its own satellite launch in a bid to join the global space club.
The attempt was postponed at the last minute due to a technical problem and a new mission date has yet to be finalised.