Mountain Valley Pipeline suspends some construction activities

The

says it is suspending some construction activities that could threaten endangered species or critical habitat areas.

The company detailed what it described as a voluntary suspension in a letter filed with the Federal Energy Regulatory Commission Thursday.

It's unclear how much of the project is covered by the announcement. And MVP says it will continue work that's necessary to stabilize and restore previously disturbed areas.

In the letter to FERC, MVP said it has cleared, graded and trenched a large majority of the 303-mile project right-of-way. The company said it has laid about 238 miles of pipe.

Earlier this week, conservation groups including the Sierra Club filed a lawsuit challenging the U.S. Fish and Wildlife Service's approval of the project.

Opponents responded to MVP's announcement, saying it shows the company knows construction poses a dire threat. And they called on federal regulators to put a stop to the project.