One person briefed by the Trump campaign said Lucas is a “front-runner” for the Interior secretary job. The person, who was granted anonymity to talk about private discussions, added that Trump wants a “more business-friendly and business experience-heavy cabinet.”

But environmentalists quickly excoriated the idea of an oil industry executive leading the department that oversees national parks and wildlife refuges, along with decisions about offshore drilling, fracking regulations and protections for endangered species.

“Putting an oil executive in charge of our public lands and precious coasts in places like North Carolina, Virginia and Florida is a virtual guarantee that Trump’s promise to throw open season on drilling in our special places will come true if he’s elected,” said Khalid Pitts, the Sierra Club’s national political director.

David Turnbull, the campaigns director at anti-fossil-fuels group Oil Change USA, worried that Trump’s Cabinet could be full of people with ties to the oil industry. They include Harold Hamm, the CEO of Oklahoma oil company Continental Resources, who has emerged as a possible pick for Trump’s energy secretary.

“Catering to an industry dead-set on continued expansion of oil and gas drilling is not only totally out of step with climate science, but it’s also out of step with the majority of Americans who are calling for a swift transition to clean energy and robust action on climate change,” Turnbull said in an email.

It would be nearly unprecedented for major oil executive to get the top job in the Interior Department. Current Secretary Sally Jewell was an engineer for Mobil Oil early in her career and often touts her experience fracking wells, although she is best known as a conservationist and former outdoor retail executive.

Lucas’ nomination would be a coup for the oil and gas industry, which has battled President Barack Obama’s Interior Department for years over everything from Endangered Species Act listings to access to federal lands for drilling. Trump has cultivated close ties to the oil industry, which was once skeptical of his campaign for president.

“In a lot of ways, having an oil and gas friendly person in the Interior Department is more important to the oil and gas industry than having someone friendly at the Energy Department,” one industry official said.

Nominating Lucas would also break with the long-standing tradition of Interior secretaries coming from Western states.

It would also likely draw rebukes from animal rights groups. Lucas, who owns a ranch and serves on Trump’s agriculture advisory committee, is one of the biggest donors to groups that attack the Humane Society and People for the Ethical Treatment of Animals, and defend animal agriculture, hunting, meat consumption, rodeos and circuses.

Another source with knowledge of the transition operation said Lucas was on a short list of about five names that are under consideration for the post, which has started to attract considerable interest from prominent “anti-conservation zealots.” Donald Trump Jr., an avid hunter, has also publicly expressed interest in the job.

Earlier this year, Lucas financed and produced a feature film called “The Dog Lover,” which portrays dog breeders and puppy mills as being unfairly targeted by animal rights groups. The movie was backed by Protect the Harvest, a nonprofit founded and chaired by Lucas, that says it’s “Keeping America Free, Fed & Fun!” In 2014, Lucas gave $250,000 to the Protect the Harvest PAC, records show.

Roger Ebert’s website called the movie “shamelessly manipulative” and “a pretty bald piece of anti-[Society for the Prevention of Cruelty to Animals] and/or PETA propaganda,” noting that the movie ends with a call to moviegoers to look into animal welfare groups before donating to them.

Animal rights supporters were quick to point out Monday that Lucas had put up hundreds of thousands of dollars into fighting an “anti-puppy mill” ballot measure in Missouri that was approved by voters in 2010.

“Forrest Lucas is a peevish advocate of trophy hunting, puppy mills and big agribusiness, and has never met a case of animal exploitation he wouldn’t defend,” said Michael Markarian, president of the Humane Society Legislative Fund, which backed the measure in Missouri.

Lucas’ wife, Charlotte, who co-founded Lucas Oil, came under fire in 2014 for a Facebook post that criticized Muslims and atheists. “I’m sick and tired of minorities running our country!” she wrote, according to news reports at the time. She later apologized.

Lucas has donated more than $150,000 to a slew of Republican candidates and causes since 2006, but records do not show any donations to Trump. In an interview last year, Lucas did not sound particularly enthused about the New York City real estate mogul.

Asked if he would be comfortable with Trump getting the GOP nomination, Lucas responded: “It would be like when Obama got elected. I’d say, ‘I don’t really like it, but I have no choice and I’ll have to make the best of it.’”

A Trump campaign spokeswoman did not respond to a request for comment. Lucas could not immediately be reached and his office did not immediately respond to a request for comment.

Elana Schor contributed to this report.