A U.S. Appeals Court late last week rejected a challenge to federal approvals for the Mountain Valley Pipeline, in a decision that likely will end legal fights over the construction of the $6.6 billion, 490-km natural gas pipeline project led by Equitrans Midstream.

As a three-judge panel of the 4th U.S. Circuit Court of Appeals in Richmond, Virginia, said: “There is no longer a live controversy” to consider after Congress in May passed a law expressly ratifying approvals for the 490-km pipeline running through West Virginia and Virginia.

A representative for the developer said it is "committed to finalizing" work on the project by the end of 2023.

The pipeline was initially projected to be finished by late 2018 but was delayed by opposition from groups that claimed it would cause environmental damage and increase the use of climate change-causing natural gas.

Proponents of the pipeline claim it is key to unlocking more gas from Appalachia, the biggest shale gas-producing basin in the United States.

Mountain Valley is owned by units of Equitrans Midstream, the lead partner building the pipeline, as well as NextEra Energy, Consolidated Edison, AltaGas and RGC Resources among others.