The same environmental group accused of being overly combative toward developer Jon Cronin’s proposed 150 Seaport development now has a state-approved waterfront zoning plan in its crosshairs.

The Conservation Law Foundation sent a letter to Massachusetts Secretary of Energy Matthew Beaton asking him to reconsider his approval of the Downtown Waterfront Municipal Harbor Plan that would enable developer Don Chiofaro to move forward with a planned 600-foot tower near Harbor Towers and for a 305-foot tower to go up on the Hook Lobster property. The nonprofit group says Beaton’s approval violated state law, the Boston Globe reports.

The organization says the new zoning doesn’t require enough open space and would allow too much height on the waterfront. It also chides the zoning for getting only $14.4M in community benefits, which is mainly tied to renovating Central Wharf by the New England Aquarium.

The CLF letter doesn’t explicitly threaten legal action, but it does mirror steps the organization took with Cronin’s development prior to suing the state, which stalled 150 Seaport for a year before getting a $13.1M settlement that will go toward children’s programming, a waterfront park and a public dock.

CLF President Bradley Campbell has come under fire in recent weeks for being too antagonistic in negotiations with City Hall. Neighbors in support of the Cronin project openly questioned if Campbell was simply trying to stop the project instead of negotiate with the developer. Linda Dorcena Forry, a former state senator, criticized him for continuing to oppose 150 Seaport after it had support from the city, state and South Boston neighbors.

Another negotiation at City Hall ended with Mayor Martin Walsh walking out of the meeting due to frustration from Campbell’s allegedly combative approach. The mayor complained in a January letter that he was concerned CLF and Campbell would mar future development and dissuade builders.

The new waterfront fight hints Campbell isn’t ready to back down.