Okla. Stat. tit. 47 § 11-311
Whenever any highway has been divided into two or more roadways by leaving an intervening space or by a physical barrier or clearly indicated dividing section so constructed as to impede vehicular traffic, every vehicle shall be driven only upon the right-hand roadway unless directed or permitted to use another roadway by official traffic control devices or peace officers. No vehicle shall be driven over, across or within any such dividing space, barrier or section, except through a permanent opening in the dividing space, barrier or section or at a permanent cross-over or intersection as established unless specifically prohibited by public authority. No vehicle shall be driven over, across or within any temporary opening in a dividing space, barrier or section or at a temporary cross-over or intersection unless specifically authorized by a public authority or at the direction of a peace officer.
Okla. Stat. tit. 47, § 11-311