Union workers at a petrochemical plant that President Trump visited in Pennsylvania were told they had to use paid time off or receive no pay for the day if they did not attend his remarks.

Ray Fisher, a spokesman for Shell, told the Pittsburgh Post-Gazette that workers have a 56-hour workweek that includes 16 hours of overtime.

Those who attended Tuesday’s event at the Royal Dutch Shell plant and also worked Friday would meet the threshold to receive all the overtime. Those who didn’t attend the White House event would not, despite both groups not working that day.

"Your attendance is not mandatory. This will be considered an excused absence. However, those who are NOT in attendance will not receive overtime pay on Friday," read a memo given to the workers, according to CNN.

Shell said it did not write the memo but confirmed that workers would not be paid the full 16 hours of overtime if they did not go to the event.

"It was understood some would choose not to attend the presidential visit and were given the option to take paid time off (PTO) instead. As with any workweek, if someone chooses to take PTO, they are not eligible to receive maximum overtime," Shell spokesman Curtis Smith said.

Some of the workers were also told not to protest the president. Smith said the memo given to employees was different than the one released by the company and did not include language about protesting.