Updated

North Korea is about a month away from launching a missile or a rocket, but U.S. officials are monitoring its coastal launch site for indications it could come more quickly, a senior U.S. intelligence official told The Associated Press.

The estimate that the launch is a month away is at odds with analysis from private imagery specialists who have scoured commercial satellite imagery of the site taken Feb. 17-18.

Pyongyang announced Tuesday that it is preparing to launch a satellite after vowing last week that it would press ahead with a missile test. The threats were made after Secretary of State Hillary Rodham Clinton urged the North to stop its "provocative actions," saying a missile test would "be very unhelpful."

North Korea said last week that it has the right to "space development" — a term it has used in the past to disguise a missile test as a satellite launch. In 1998 North Korea test-fired a shorter-range Taepodong 1 missile over Japan, claiming at the time to have put a satellite into orbit.

Jane's Defense Weekly said last week that based on the activity at the site on North Korea's east coast, North Korea could be preparing for a missile launch within days.

But the senior U.S. intelligence official said this week threw doubt on an imminent North Korean launch.

"Indicators of potential launch light up more each day, but we're still a ways off," the intelligence official said, speaking on condition of anonymity because he is not authorized to speak to the press.

The open-source images became available last week after reports from South Korean and Japanese intelligence agencies suggesting that a launch was coming.

The commercial satellite images, captured by DigitalGlobe, are the most recent publicly available photos of the Musudan-Ri site. One image shows a missile launch tower but shadows obscure details.

Independent analysts last year used similar commercial images to reveal a secret North Korean missile base that is being constructed on the country's west coast.

No missile or rocket appeared to be on the launch platform as of Feb. 18, said Tim Brown director of Talent-Keyhole.com, an independent imagery analysis firm. A second shows a large horizontal vehicle checkout building surrounded by people and vehicles.

"There's more activity here than I have seen in two or three years," said Brown. "I'd anticipate a launch within weeks, not days."

The North Korean announcement follows a report by the South Korea's Defense Ministry Monday that North Korea recently deployed a new type of medium-range ballistic missile capable of reaching northern Australia and the U.S. territory of Guam.

These new medium-range ballistic missile can travel at least 1,800 miles, which would put the Pacific island of Guam, the northern tip of Australia and much of Russia and India within striking distance, the ministry said in a defense assessment of North Korea issued every two years.

The announcement came on North Korea leader Kim Jong Il's 67th birthday. Kim Jong Il was believed to have had a stroke last fall, but U.S. intelligence officials report he has recovered and apepars to be in firm control of the country.