JOLIET, Ill. (AP) _ Caterpillar Inc. and officials of the striking machinists union have agreed to meet with a federal mediator, union officials said.

The mediator, Bill Sigler, contacted Local 851 of the International Association of Machinists and Aerospace Workers and Caterpillar on Wednesday to encourage negotiations, said union spokesman Joe Misener.

A meeting was set up for Friday morning, he said. Caterpillar spokesman Bill Stran confirmed the meeting.

With tension on the picket lines growing, Caterpillar officials told union members that they intend to seek a temporary restraining order to limit the number of picketers at the Joliet plant, Misener said. Stran, however, declined comment on that report and would not confirm it.

Usually there are eight picketers at each gate of the plant, Misener said, but he said there have been more.

Police were called to the plant for the second day in a row Wednesday amid reports that union members were delaying trucks from entering. There were no arrests.

About 2,400 union members have been on strike at the Joliet plant since their three-year contract expired Aug. 1, over issues of pay and working hours. There are 900 salaried workers still on the job.

The Joliet plant supplies various component parts, such as hydraulic hoses, for other Caterpillar manufacturing plants.

Union and company officials have said stumbling blocks to a settlement have been the company's proposals to extend a wage freeze imposed three years ago for another 32 months, and to schedule workers for four 10-hour days or three 12-hour days weekly, instead of the traditional five eight-hour days.