SEATTLE (AP) — Boeing is encouraging its suppliers to attend a workshop next month to learn how to outsource business to Mexico.

The Seattle Times reports that Patrick McKenna, director of Supply Chain Strategy and Supplier Management at Boeing Commercial Airplanes, has urged suppliers to attend a Nov. 15 workshop in Chicago to learn how to do business in Mexico.

“Several of our suppliers have successfully set up factories in Mexico because of the numerous advantages that Mexico offers to aerospace suppliers,” McKenna wrote in a letter dated Oct. 17. “Boeing will be sending several people to this event, and we wanted to inform our supply base of this opportunity.”

McKenna said the event’s organizers will waive the $200 registration fees for Boeing suppliers.

Boeing spends billions of dollars each year with Ohio suppliers, making Ohio Boeing’s No. 2 supplier state.

Tom Wroblewski, president of District 751 of the International Association of Machinists, said the letter undermines efforts to build the domestic workforce.

“We’d think that Boeing CEO Jim McNerney, as chairman of President Obama’s council on exports, would be particularly sensitive to the importance of exporting American products, not jobs,” Wroblewski told The Seattle Times via email, adding the union planned on speaking to Boeing about the issue.

Boeing spokesman Larry Wilson said the company often keeps suppliers informed of outsourcing opportunities.