(A)   Except when directed to proceed by a police officer or traffic-control signal, every driver of a vehicle approaching a stop intersection indicated by a stop sign shall stop before entering to crosswalk on the near side of the intersection, or the event there is no crosswalk, shall stop at a clearly marked stop line, but, if none, then at the point nearest the intersecting roadway before entering the intersection.
   (B)   The driver, after having stopped, shall yield the right-of-way to any vehicle which has entered the intersection from another highway or which is approaching so closely on the highway as to constitute an immediate hazard.  The driver having so yielded may proceed, and the drivers of all other vehicles approaching the intersection shall yield the right-of-way to the vehicle so proceeding.
(47 O.S. § 11-403(a))  (`90 Code, § 20-67)