Updated

North Korea could be ready to test-fire a missile within days as satellite imagery has shown increased activity at a missile site over the past 48 hours, a defense weekly said.

A significant increase in launch preparations has occurred at the Musudan-ni missile site on the communist country's northeastern coast, said Joseph S. Bermudez Jr., a senior analyst at Jane's Information Group who specializes in North Korean defense and intelligence matters.

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"The latest satellite images ... indicate that North Korea is preparing to launch either a prototype Taepodong 2 intermediate range ballistic missile or a Paektusan 2 space launch vehicle within a matter of days," Jane's Defence Weekly said in a report issued Friday in London.

The report comes amid growing international pressure on the North to drop its apparent plans to fire a long-range missile believed capable of reaching U.S. territory. Washington, Seoul and Tokyo have repeatedly warned Pyongyang against firing a missile, saying the move would trigger international sanctions.

Bermudez said satellite images show the activation of launch equipment and radars, and the arrival of numerous trucks and support vehicles. Support facilities for the engine test stand were undergoing expansion, the report said.

North Korea launched a failed long-range Taepodong 2 missile in 2006. That test alarmed the world and gave new energy to the stop-and-start diplomacy over North Korea's nuclear program. The North is believed to possess up to a dozen nuclear warheads.

Pyongyang also conducted a surprise launch of a Taepodong 1 missile over Japan in 1998.

In preparation for a possible launch, the U.S., Japan and South Korea have increased intelligence collection efforts, including increased sorties of reconnaissance aircraft and the deployment of Aegis-equipped naval vessels and specialized reconnaissance ships, the Jane's report said.

North Korea has said it has the right to "space development" — a term the country has used in the past to disguise a missile test as a satellite launch. When North Korea test-fired the missile in 1998, it claimed to have put a satellite into orbit.

On a regional tour, U.S. Secretary of State Hillary Rodham Clinton urged the North to halt "provocative actions," noting Friday such a missile test would violate a 2006 U.N. Security Council Resolution banning Pyongyang from pursuing missile or nuclear programs.