A new federal review of pipeline approvals could set up a fight between environmental groups, with some calling the review a "wolf in sheep’s clothing" while questioning the praise of other green groups as "sick" and troubling.

Environmental activists say the Federal Energy Regulatory Commission's recently announced review of its pipeline approval policy marks the next step in the Trump administration's "dirty energy agenda," while other groups such as the Natural Resources Defense Council said they were encouraged by the review.

“I was sick when I saw a positive statement from some groups about this review," said Maya van Rossum, head of the Delaware Riverkeeper Network, a key opponent of pipeline expansion. "I believe this process will be used to further advance pipelines and further empower pipeline companies, and it will be very bad for states’ rights, people’s rights, property rights and the environment."

Kevin McIntyre, the commission's Trump-appointed chairman, proposed last week to take a "fresh look" at the 1999 natural gas pipeline review process. “I am approaching this topic with an open mind and want the staff and the commission to take a fresh look at all aspects of the issue,” McIntyre said.

Jeff Tittel, the head of Sierra Club's New Jersey chapter, called the FERC review the exact opposite of how the commission described it.

"This FERC proposal is a wolf in sheep’s clothing," Tittel said Tuesday, calling it "nothing but cover" to help the administration "streamline pipelines while pushing for coal and subsidizing nuclear power and blocking renewable energy."

Tittel was referring to FERC's separate review of Energy Secretary Rick Perry's grid regulation proposal to provide market incentives for coal and nuclear power plants. FERC is expected to decide on the electricity proposal next month.

McIntyre's pipeline review "is part of the Trump administration’s dirty energy agenda," Tittel said. "Kevin McIntyre was appointed head of FERC because he will further that agenda."

“FERC is nothing, but a rubber stamp for the industries its supposed to regulate, and we won’t believe that anything will change with this review of policies, at least not under the Trump administration,” Tittel said.

The Natural Resources Defense Council, a prominent environmental group, said it was encouraged by McIntyre's announcement.

Montina Cole, an attorney with the group, said McIntyre's announcement was "very encouraging news" for a policy that has not been changed for nearly two decades "even though the energy industry is far different now."

The decision appears to match an NRDC-sponsored report from last month that recommended updating the pipeline policy.

"Overbuilding of pipelines is a serious threat given underuse of the existing system and questionable contracts where the pipeline developer acts as both seller and buyer of pipeline capacity," Cole said. "And to the extent there are unwarranted pipeline costs, utility customers could foot the bill."

NRDC does not flat out reject the review process like the other groups but wants FERC to consider the concerns being raised about new pipeline development.

"Heightened community concerns about the environment, health and safety, and taking of private property have accompanied the increase in gas pipelines," Cole said. "FERC has only rejected two of the approximately 400 pipeline applications filed since the 1999 policy was adopted."