The National Council of Dockworkers' Unions of Japan (Zenkoku Kowan) and the All Japan Dockworkers' Union (Kowan Domei) began flexing their muscle on Mar. 5 in an attempt to ward off possible deregulation of Japan's ports.

The groups announced that they will stage a 24-hour strike Mar. 12, which would completely stop all cargo-handling activities at the nation's 50 ports, and cease working Sundays beginning March 16. A one-year agreement concerning Sunday work, which has been extended twice in the past, is due to expire on Mar. 10. The two groups are made up of 55,000 dockworkers, 45 percent of Japan's total.

The unions are protesting the government's position toward deregulating ports and criticizing the European Union and the United States for pressuring Japan to change long-standing practices that drive up shipping costs. The labor unions are also asking for improved working conditions such as fewer hours and higher wages. Union officials said that deregulation will intensify competition and will worsen working conditions.