North Korea's apparent preparations for a ballistic missile test, reportedly detected by South Korean officials monitoring a train headed to a launch site, appear to be the country's latest attempt to get President Barack Obama's attention.

A South Korean official on Tuesday confirmed the preparations, first reported by Japanese and South Korean media citing sources as saying the missile had the potential to reach the western United States.

"There are signs North Korea is preparing for a missile launch," the intelligence official told The Associated Press. He declined to give further details and spoke on condition of anonymity, citing the sensitivity of the issue.

South Korean intelligence has spotted a train carrying a long, cylinder-shaped object — believed to be a long-range missile — heading to a new launch site on North Korea's west coast, South Korea's Yonhap news agency reported.

North Korea's clandestine missile program has been a key regional concern, along with its nuclear weapons program.

However, North Korea is not believed to have acquired the technology to develop a nuclear warhead light enough to be mounted on a missile, another South Korean intelligence official said. He would not give his name, citing department policy.

The move comes amid heightened tensions on the Korean peninsula, with the North declaring last week that it was abandoning pacts designed to prevent hostilities with the South. Relations between the Koreas have been tense since South Korean President Lee Myung-bak took office a year ago with a tough new policy on Pyongyang.

Obama has told Lee that Secretary of State Hillary Rodham Clinton will visit Seoul in mid-February.

Intelligence indicates the object spotted in North Korea is likely a long-range Taepodong-2 model, Yonhap said. The North could complete preparations for a missile launch within one or two months, the report said, citing unidentified officials.

South Korea's Defense Ministry declined to comment on Yonhap's report.

Any missile launch would be aimed at drawing Washington's attention, as well as pressuring Seoul into softening its policy on Pyongyang, said Park Jung-chul, a North Korea expert at the government-funded Korea Institute for National Unification.

"It's designed to draw U.S. interest at a time when the North's nuclear program is being sidelined by the global financial crisis and the conflict in the Gaza Strip," Park said.

North Korea appears to be "reminding" Obama it has long-rang missiles and nuclear capability, said Paik Hak-soon, an analyst with the private Sejong Institute security think tank.

"North Korea is taking political action," he said.

The Taepodong-2 — considered the North's most advanced rocket — has a range of more than 4,160 miles, putting Alaska in range.

However, the missile being readied may be an upgrade of the Taepodong-2, said Koh Yu-hwan, a North Korea expert at Seoul's Dongguk University. The North reportedly has been trying to develop an advanced version of Taepodong-2 capable of striking the west coast of the mainland United States.

Japanese government officials also cited preparations for the launch of an upgraded Taepodong-2, the Sankei newspaper reported in Tokyo. Officials at Japan's Defense and Foreign ministries could not be reached for comment Tuesday.

In 2006, the North launched a Taepodong-2 missile from its east coast site in Musudan-ni. The rocket plunged into the ocean shortly after liftoff.

Last year, North Korea tested the engine of a long-range missile, indicating progress in developing a new missile, U.S. and South Korean officials said.

Koh said he doubted Pyongyang would fire a missile any time soon because a test could derail its goal of establishing relations with the Obama administration.

"North Korea has nothing to gain" from a missile launch right now — but could fire off a missile if negotiations with Washington do not go well, Koh said.