PORTLAND, Maine (AP) Maine’s Democratic governor has vetoed a bill that concerns the future of offshore wind development in the state.

Conservationists and labor leaders tout expansion of offshore wind in Maine, and Gov. Janet Mills has made it a focus of her tenure. The Maine Legislature passed a bill to modify visual impact standards to help encourage more development of wind power.

Lawmakers also amended the bill to require the wind projects to have labor agreements. Mills did not support that idea, and vetoed the bill Monday.

Mills wrote in her veto message that she is generally supportive of labor agreements but feared in this case that the change could “stifle competition, which could cut out thousands of workers and employee-owned businesses.” She also said she feared it could favor out-of-state unions over local companies and workers.

Both sides expressed hope that they can save the bill before the end of the legislative session, which is coming soon. However, labor leaders and some Democrats said they were disappointed in the veto.

Democratic State Sen. Chip Curry said the veto “threatens this new industry, putting good jobs for Maine people and the environmental benefits that go along with offshore wind at risk.”