Updated

The Standing Rock Sioux Tribe must have a say with regard to a $3.8 billion oil pipeline that could disturb sacred sites and impact drinking water for 8,000 tribal members, representatives of the United Nations Permanent Forum on Indigenous Issues said Wednesday.

In a statement, the forum's chairman Alvaro Pop Ac called on the U.S. to provide the tribe a "fair, independent, impartial, open and transparent process to resolve this serious issue and to avoid escalation into violence and further human rights abuses."

Dalee Dorough, an Inuit member of the forum, which provides representation at the world body for indigenous peoples around the globe, said failure to consult with Sioux over the project violated the U.N. Declaration on the Rights of Indigenous Peoples.

Article 19 of the declaration, which the U.S. endorsed in 2010, says: "States shall consult and cooperate in good faith with the indigenous peoples concerned in order to obtain their free, prior and informed consent before adopting and implementing legislative or administrative measures that may affect them."

"There has been a lack of good faith consultation with the indigenous people who will more than likely be impacted," Dorough said in telephone interview from Anchorage Alaska. "The U.N. declaration is fundamental because President Obama pronounced support for it and that they haven't been consulted consistent with the rights of that declaration is highly problematic."

Native Americans from reservations hundreds of miles around have joined the growing protest against the Dakota Access Pipeline, which will pass through Iowa, Illinois, North Dakota and South Dakota, causing the company to temporarily halt construction. Over the past few weeks, nearly 30 protesters have been arrested.

On August 25, 2016, the Standing Rock Sioux and hundreds of people gathered in Washington D.C. in opposition to the construction of the Dakota Access Pipeline. A judge is expected to rule on a lawsuit submitted by the Sioux against the Army Corps of Engineers for lack of consultation.