Vice Marshal Kim Yong-chun, 73, who for two years has been one of Kim Jong-il's right hand men, was named on Wednesday to replace Kim Il-chol, defense minister since 2000. Kim Yong-chun received his rank of marshal in 1995.
South Korean observers have noted that North Korea's Defense Ministry is subordinate to the country's communist nation's Defense Committee and is not a part of the Ministerial Cabinet as it was earlier, when changes in the ministry were made exclusively by the parliament. This time the change was made by Kim Jong-il personally.
Over the last few days, North Korea has been creating tension with its southern neighbor by preparing missile launches and threatening to reduce South Korea to ashes. Some analysts believe that the North is trying to get Washington's attention so that it puts pressure on Seoul to ease its strict policies on its neighbor.
The Yonhap news agency quoted a defense source in Seoul last week as saying U.S. and South Korean intelligence officials had recently identified a North Korean train carrying what was believed to be a Taepodong-2 missile. The source said that this could indicate the likelihood of a launch taking place in a month or two.
The Taepodong-2 has a range of up to 6,000 km (3,700 miles) and could therefore, in theory, reach the U.S. states of Alaska or Hawaii.
A Taepodong-2 missile, which can carry a payload of up to 500 kilograms, was last test launched in July 2006, a few months before the isolated communist state tested a nuclear bomb, although it reportedly malfunctioned 40 seconds into the flight.
Relations between Seoul and the communist Pyonyang have deteriorated since South Korean President Lee Myung-bak took office in February 2008.
After coming to power last February, Lee said he would review agreements reached at the 2000 and 2007 inter-Korean summits, and demand more in return from the North for the economic support provided by Seoul.
North Korea said on Friday it would scrap all political and military agreements with South Korea, including a non-aggression pact, over its neighbor's "hostile intent."
The two countries are still technically at war as their 1950-53 conflict ended in a truce rather than a peace treaty.