More than 20 entertainment unions, including those affiliated with the Los Angeles County Federation of Labor, Thursday approved sanctions that would prevent their members from filling jobs held by members of the Directors Guild of America in the event of a DGA strike. The federation's executive committee is expected to add its endorsement, federation Secretary-Treasurer William Robertson said. Union members may individually choose not to cross picket lines, but union leaders are contractually prohibited from ordering such a move, he added. DGA President Gilbert Cates said Thursday that no progress has been made in the "painful" negotiations between the DGA and the Alliance of Motion Picture and Television Producers. The DGA's contract expires Tuesday. Among unions endorsing the sanction: the Screen Actors Guild, the Screen Extras Guild, the Writers Guild of America and the International Alliance of Theatrical Stage Employees.