Residents of other major cities could follow suit later, the Tokyo Shimbun newspaper reported on Feb. 18.
The North's security agency believes a cell phone was used as a detonator in the 2004 blast because a mobile phone with adhesive tape attached to it was found in the debris at the rail station in the town of Ryongchon, near the border with China.
Mobile calls were also blamed for the leak of news about the explosion that killed about 170 and injured 1,300.
Kim Jong-Il's special train passed through Ryongchon from Beijing just hours before the explosion, triggering speculation that the blast may have been linked to an assassination attempt.
Despite the ban, however, some North Koreans such as border traders have continued to use mobile phones, making use of Chinese cell phone networks, according to intelligence sources in Seoul.
Some made cell phone calls to relatives in the South. Chinese communication companies, which have rapidly expanded their cell phone services, have installed relay stations along the border with North Korea.
The North has increased public executions and toughened punishments against those caught owning mobile phones, according to a recent human rights white paper published by the sate-run Korea Institute for National Unification.
Cell phones have become more essential to North Korean officials and merchants after North Korea recently tightened border controls.
The lifting of the ban comes after the North allowed Egypt's Orascom Telecom to invest up to $400 million to set up a mobile telephone network in the communist country.
Orascom, the largest mobile communications company in the Middle East, said last month that it has formed a joint venture with the North's state-run Korea Post and Telecommunications Corp. for the mobile phone service.
An intelligence source in Seoul said the Orascom phones would probably not be able to make international calls because the North has made efforts to prevent outside information from coming into the closed society.
North Korea is also seeking to shift the technology used for wireless phone calls from the European-style global system for mobile communications (GSM) to American-style code division multiple access (CDMA) due to security concerns, the source said. GSM is more prone to eavesdropping.
North Korea introduced mobile phone service in November 2002, with cell phones from Motorola and Nokia. The number of mobile phone users increased to more than 20,000 in 2003, according to Chosun Sinbo, a newspaper run by pro-Pyongyang ethnic Koreans in Japan.