The Native American tribe at the center of protests against an oil pipeline in North Dakota reacted angrily Wednesday to the resumption of construction on lands the tribe considers sacred.

The US government has twice asked the operators of the Dakota Access Pipeline to voluntarily pause construction near the tribe's reservation, while authorities reconsider the pipeline's route.

The latest request came Monday, after a weekend appellate court decision refusing to compel Energy Transfer Partners to halt construction within 20 miles (32 kilometers) of the disputed area.

The company resumed construction Tuesday, on what the Standing Rock Sioux Tribe says is land that contains ancient and sacred sites. The tribe also contends that the project threatens its drinking water supply.

"They have bulldozed over the burials of our Lakota and Dakota ancestors and have no regard for the sanctity of these places," Dave Archambault, the Standing Rock Sioux Tribe chairman, said Wednesday.

He urged President Obama to take action to stop the company.

"We need him to take action now. Our lives are at risk and the places we hold sacred are at risk. Millions have stood with us in opposition to this pipeline and he must heed their call," Archambault said.

Energy Transfer Partners said the pipeline, which snakes through four states, has complied with the law. The views of tribes that participated in the project planning process were considered, the company said in a statement, adding that the project was "reviewed and approved by highly qualified private and state-employed archeologists."

"We reiterate our commitment to protect cultural resources, the environment and public safety," the company said.

The Dakota Access Pipeline has been the subject of a months-long protest in North Dakota. Native Americans and their supporters have camped outdoors to block the pipeline's route underneath the Missouri River and the adjoining man-made Lake Oahe.

The standoff has grown into a larger protest movement in the United States, drawing in Indian tribes, environmentalists and advocates for Native Americans.

There have been repeated clashes in the last several months between pipeline workers and protesters. Local authorities have arrested at least 123 people since August.

In a Wednesday email, Morton County Sherriff's office spokeswoman Donnell Hushka characterized the ongoing protests as a "hostile situation" and said officers and media on the scene had encountered "threatening behaviors."

During a protest Monday, actress Shailene Woodley, of the "Divergent" film series, was one of 27 arrested. She was charged with criminal trespass and engaging in a riot, and is due in court on October 24, police said.