Ford has cut ties with the controversial lobby group Alec, joining a roster of big corporations that have distanced themselves from the rightwing network that promotes policies at the state level to counter environmental regulations.

The car giant confirmed to the watchdog the Center for Media and Democracy (CMD) that it had ended its membership. A company spokesman said that “we will not be participating in Alec in 2016”.

Ford did not specify the reason for the split other than to say that it flowed from an “annual budget review”.

Ford’s departure from the American Legislative Exchange Council puts it in league with other massive corporations that in recent months have concluded that association with the lobbying network is more trouble than it’s worth. Other big firms that have similarly broken connections include the technology companies Google, Facebook, eBay and Yelp, as well as the energy giants Shell and BP.

Ford strongly publicizes its support for environmental sustainability, which it says it has put at the heart of its business model. It advocates fuel economy in its cars and says it is working to reduce greenhouse gas emissions.

Such a public stance conflicts with the work of Alec, which has used its muscle as match-maker between state politicians and big businesses to push back on environmental controls. The group operates by producing so-called “model bills” that are favorable to big corporations that it then disseminates in state assemblies across the country.

The Guardian revealed that part of the group’s anti-green agenda was to agitate to make it more difficult for homeowners to install solar panels. Several of its model bills aim to block federal efforts by the Environmental Protection Agency to cut back on emissions from energy creation under the Clean Power Plan.

In its model bill on research on climate change, Alec says that “human activity has and will continue to alter the atmosphere of the planet” and that such activity may lead to warming of the planetary temperature. But it goes on to suggest that “such activity may lead to deleterious, neutral, or possibly beneficial climatic changes”.

Even more contentiously, the lobby group goes on to state that “a great deal of scientific uncertainty surrounds the nature of these prospective changes, and the cost of regulation to inhibit such changes may lead to great economic dislocation”.

Ford’s funding of Alec was first disclosed by CMD last November. Nick Surgey, the watchdog’s director of research, said that “Ford appeared to be very happy to quietly fund Alec when its membership was secret, but now that the relationship has become public it has become a liability”.

Alec professed to be unflustered by the departure of Ford from its corporate membership. The group’s spokesman Wilhelm Meierling told the Guardian that the car company had made the decision to withdraw last year at a time when Alec gained more than 30 other private sector members.

“It’s an exciting time to be at Alec, with private sector growth in a variety of sectors including renewable energy,” Meierling said.