Omaha, NE (AP) – The proposed $85 billion merger of the Union Pacific and Norfolk Southern railroads has lost the support of two unions that represent more than half their workers.

The unions representing engineers and maintenance workers worry the deal will jeopardize safety and jobs, and lead to higher shipping rates and consumer prices. They are now among the most prominent critics of this deal.

But the deal does have the support of the nation’s largest rail union that represents conductors and hundreds of individual shippers. The U.S. Surface Transportation Board will weigh the opinions of all stakeholders to determine if the merger is in the public interest.

This story may be updated.