BISMARCK, N.D. (AP) — A government order for protesters of the Dakota Access pipeline to leave federal land could have little immediate effect on the encampment where hundreds of people have been gathered for months to oppose the $3.8 billion project.

A North Dakota sheriff says the deadline is meaningless and serves only to reduce the government’s legal responsibility for demonstrators.

The Corps says all federal lands north of the Cannonball River will be closed for “safety concerns” starting Dec. 5. The order includes the large encampment known as the Seven Council Fires camp.

The agency cited the approach of winter and increasingly contentious clashes between protesters and police.

But the Corps says it has no plans to forcibly remove anyone. Violators could be prosecuted for trespassing.