CALGARY - Developers have halted work on part of a major pipeline project in North Dakota that Enbridge Inc. recently announced it would spend US$1.5 billion to buy into.

The US$3.7-billion Dakota Access Pipeline is set to run through four states and has faced protests and opposition over concerns about environmental impacts.

The Standing Rock Sioux Tribe in southern North Dakota sued federal regulators last month for approving the pipeline, arguing it would affect drinking water and disturb sacred sites.

Dallas-based Energy Transfer Partners said Thursday it will stop work near the reservation until a temporary injunction hearing next week, but that work continues in other parts of the state.

Calgary-based Enbridge (TSX:ENB), through its affiliate Enbridge Energy Partners, announced on Aug. 2 that it would acquire a 27.6-per-cent indirect interest in the Bakken pipeline system that includes the Dakota Access pipeline.

At the time, Enbridge said it would re-evaluate and end joint-venture agreements on its delayed $2.6-billion Sandpiper Pipeline project if the deal involving the Dakota Access pipeline goes through.

The 1,886-kilometre Dakota Access pipeline is designed to carry 470,000 barrels of oil a day from production fields in North Dakota to Patoka, Ill.

With files from The Associated Press.