The council shall determine those intersections at which drivers of vehicles shall not make a right, left, or U-turn and shall place proper signs at these intersections. The making of the turns may be prohibited between certain hours of any day and permitted at other hours, in which event the hours shall be plainly indicated on the signs or they may be removed when the turns are permitted. Restrictions on turning movements shall be as specified in appendix I, sections 119 through 121 hereby incorporated herein.