The $66.8 billion deal NextEra Energy proposed last month to buy Dominion Energy and create the largest regulated electric utility in the US would consolidate too much power into too few hands, said Sen. Angus King, a Maine independent who caucuses with Senate Democrats.

King, who is the ranking member of the Senate Subcommittee on Energy and Natural Resources, urged FERC not to approve the purchase, according to Reuters.

King said in a filing that a utility company of that size would wield undue influence over regional energy markets. He added that NextEra lobbied in New England against clean energy competition.

According to the proposed deal, the combined company would be more than 80% regulated, serve about 10 million utility customer accounts across Florida, Virginia, North Carolina and South Carolina and own 110 GW of generation across a mix of energy sources. 

For customers, the deal proposes $2.25 billion in bill credits spread over two years after closing for Dominion Energy's customers in Virginia, North Carolina and South Carolina, according to a release from NextEra.

The deal is tax-free to shareholders and immediately accretive at closing to adjusted earnings per share, according to NextEra. NextEra and Dominion shareholders would own about 74.5% and 25.5% of the combined company, respectively.