HARTFORD, Conn. – A Boston environmental group is challenging how energy policy is coordinated by New England’s six governors, saying the state leaders are conducting private negotiations with the energy industry.

The Conservation Law Foundation has submitted public records requests in the region’s six states. It said a plan by the governors that focuses on natural gas and hydropower from Canada “appears to be the product of backroom deal-making rather than sound public policy informed by open dialogue.”

The group’s vice president of policy and climate advocacy, Seth Kaplan, said, “Without vital public transparency, the resulting projects are sure to cost more than they should, in dollars as well as environmental impact.”

The governors late last year announced a plan to expand natural gas use. They asked the region’s grid operator, ISO-New England, for technical help to seek proposals to build transmission equipment and public works to deliver electricity to as many as 3.6 million homes. They also asked ISO to figure out how to finance the project.

Christopher Recchia, commissioner of Vermont’s Public Service Department, said state officials have been transparent since announcing the initiative and actions in the future will be “entirely public.”

“There is no basis for this to be considered not out in the open,” he said.

Dennis Schain, the spokesman for the Connecticut Department of Energy and Environmental Policy, and Krista Selmi, spokeswoman for the Massachusetts Executive Office of Energy and Environmental Affairs, said the governors have had a policy of openness. They issued a public statement about the initiative in December, published their request to ISO-New England for technical assistance in January and initiated a comment process this month.

“You don’t need to look any further than the price spikes for electricity in the Northeast this winter to appreciate the pressing need for action to correct decades of inactivity when it came to expanding both regional electric transmission capability and natural gas pipeline capacity to supply power plants,” Schain said.

Patrick Woodcock, director of the Maine governor’s energy office, said the states have solicited information from numerous groups “from the moment this initiative was created,” and he denied that state officials have negotiated privately with the energy industry.

Behind the Conservation Law Foundation’s criticism of the policy-making process is its difference with governors over what it believes is an over-reliance on natural gas. It’s touted as less expensive than heating oil, but the drilling method used to draw out natural gas known as fracking is bitterly denounced by environmentalists.

“The assumption which seems to be going on here is that we need a great new pipeline that must be paid for by the customers of New England through our electricity bills,” Kaplan said. “That assumption we think is wrong and at the very least needs to be tested in public.”

Demanding records and emails that may detail issues raised between the governors, their environmental officials and others might shed light on how the region’s energy policy is being developed, he said. Specifically, what are now private communications could provide information on internal debates, Kaplan said.

“We suspect that different states want different things. Some may not be on board on this. They might be quietly acquiescent. We don’t know,” he said.

Recchia said the governors and top environmental officials have only recently kicked off debate over hydropower, wind power, natural gas and other sources of energy.

“We’re just in the beginning stage,” he said.