de·rec·og·nize 
(dē-rĕkəg-nīz′)
(dē-rĕkəg-nīz′)tr.v. de·rec·og·nized, de·rec·og·niz·ing, de·rec·og·niz·es
To rescind formal, especially diplomatic recognition of: a proposal to derecognize the outlaw terrorist state.
de·rec′og·nition (-nĭshən) n.