The United States and the Soviet Union have agreed to destroy their remaining stocks of live smallpox virus by the end of 1993, the World Health Organization said Friday.

The nations held the virus stocks, frozen in top security labs, for possible use in biological warfare. WHO announced the world was free of smallpox in October 1979. No case of the disease has been confirmed since.U.S. and Soviet officials confirmed their countries have stopped vaccinating soldiers against smallpox, a WHO statement said.

The 11-member WHO smallpox committee agreed all stocks of the virus must be destroyed by Dec. 31, 1993. The agency said this will end fears of accidental infection or intentional misuse.