North Korea's government has confirmed suspicions that it is preparing for a long-range rocket launch.

The International Maritime Organization said Tuesday that the regime in Pyongyang had informed it of plans to launch a satellite between Feb. 8 and Feb. 25.

The U.S. and other western governments view North Korea's satellite launches as loosely-veiled tests of its long-range missile technology, and Kim Jong Un's government has been warned that any such move would be considered a further provocation on the heels of the regime's most recent nuclear test.

The U.S. and its allies are still formulating their response -- and trying to work out differences with China, North Korea's closest ally -- to the nuclear test carried out in January. That test, which American officials do not believe was of a device nearly as powerful as the hydrogen bomb touted by North Korea, was a violation of United Nations sanctions against the isolated, totalitarian state.

Get Breaking News Delivered to Your Inbox

South Korea's Defense Ministry warned last week that the North appeared to be preparing for a long-range ballistic missile test, amid unconfirmed reports that a launch could be just days away.

"We predict that North Korea's next significant military provocation will be carried out in a surprising manner," Defense Ministry spokesman Kim Min-seok said Thursday at a news conference in Seoul. "The South Korean military is continuing to keep a close watch on any signs of North Korea's long-range missile test."

The new information, based on satellite imagery of one of North Korea's established rocket launching sites, came a day after U.S. Secretary of State John Kerry urged China to keep a lid on North Korea's military ambitions during a meeting with senior Chinese leaders in Beijing.

Kerry described North Korea's growing nuclear capability and related missile technology as a "threat the United States must take extremely seriously" during a joint news conference with his Chinese counterpart, Foreign Minister Wang Yi.

North Korea last tested a long-range missile in December 2012, when it successfully launched a Unha-3 (Galaxy 3) rocket into space, carrying a satellite.

Pyongyang insisted the launch was merely to put a weather forecasting satellite into space, but experts in the U.S. and South Korea accused the North of conducting a thinly veiled test of its intercontinental ballistic missile capability.

Analyzing the rocket debris from the launch in 2012, South Korean officials described the North as having possibly secured a missile range of up to 6,200 miles, which would put the western coast of the U.S. mainland within reach. Most experts, however, agree that North Korea has yet to master the technology to fit a nuclear warhead onto such a missile.

South Korean officials say the North completed a major upgrade last year to its main missile launch site in the country's northwest. The upgrade is believed to have extended the launch pad's height to about 67 yards, which would allow the North to launch a more powerful rocket than the Unha-3.

Many experts in South Korea see the isolated regime's continued military provocations as a carefully calculated move, with tangible objectives.

"North Korea appears to be intent on driving a wedge between the U.S. and China," Kim Han-kwon, a professor at the Korea National Diplomatic Academy, told South Korea's YTN news network. Kim said a new long-range missile test would cajole the international community to push for stronger sanctions against the North, which would force China -- fearing the North's political collapse and the mass exodus that would cause more than its military ambitions -- to fend for its treaty ally.

"From North Korea's perspective, a schism between China and the U.S. is the ideal situation," Kim said. "Because of the strategic interests at stake, China will be forced to further embrace North Korea."

CBSNews.com foreign editor Tucker Reals in London contributed to this report.