Overpopulation is hindering the Tokyo area from protecting itself from natural disasters and is causing other serious problems, a National Land Agency report warned June 13.

The 1997 white paper on development of the Tokyo metropolitan area, approved at the day's Cabinet meeting, said the population inflow into the metropolitan area -- Saitama, Chiba and Kanagawa prefectures as well as Tokyo -- exceeded the outflow in 1996 for the first time in three years. However, some 5,500 more people left Tokyo proper than moved in between April 1996 and March 1997, the white paper says.

Traffic congestion, resident concerns over a lack of antidisaster measures and other problems that arise from overpopulation are still serious problems, it says, calling for more efforts in forming a national consensus on transferring the capital's functions from Tokyo. The number of people who live in the greater metropolitan area, comprised of the Tokyo area plus Ibaraki, Tochigi, Gunma and Yamanashi prefectures, totaled some 40,550,000 as of Oct. 1, 1996, representing 32.2 percent of the nation's population, the paper says.