RENO, Nev. - A proposal from the wife of Texas billionaire T. Boone Pickens to create a sanctuary in Nevada for wild horses removed from public rangeland around the West has been rejected, the U.S. Bureau of Land Management said Friday.

Madeleine Pickens' plan wouldn't save taxpayers' money and doesn't include enough water and forage for the mustangs, agency Director Bob Abbey told The Associated Press.

He said the BLM spent considerable time with Pickens on her proposal, and is committed to pursuing public-private partnerships to improve its management of the symbols of the West.

"However, despite numerous requests from the BLM, (her) foundation has not provided a formal and detailed proposal so that the BLM can properly analyze and determine its feasibility," Abbey said.

Pickens said the BLM failed to clarify what details it wanted, but she was not giving up. She bought two ranches in northeastern Nevada last year to serve as a sanctuary for mustangs captured from the range, instead of in government-funded holding facilities.

"I'm going to keep working with the BLM," she told the AP. "It's like your children. You just have to keep working with them until they get it right. To me, it's sad we don't have the leadership to fix the issue of these poor American mustangs."

Pickens first proposed establishing the sanctuary in 2008 after the BLM said it was considering euthanasia as a way to stem escalating costs of keeping animals gathered from the open range.

The BLM rejected her initial proposal, saying it involved the use of public land where wild horses did not exist when the Wild Free-Roaming Horses and Burros Act was enacted in 1971.

While Pickens' latest proposal addresses that issue, Abbey said it would require an environmental analysis to transfer title of wild horses to her and change the class of livestock authorized on several Nevada grazing allotments from cattle to horses.

Among other reasons, existing law also would need to be changed to give the BLM the authority to reimburse a private party for grazing wild horses, he said.

Under Pickens' latest proposal, a nonprofit foundation would care for the animals with a government stipend of $500 a head, per year. Abbey said that exceeds the BLM's existing long-term holding cost of $475 a head, per year, in Midwest pastures.

"Her prospectus, as presented, does not demonstrate an obvious cost savings to the American taxpayer," he said.

But Pickens said her proposal would result in "huge savings" because it would involve the government initially turning over 1,000 wild horses in short-term holding facilities where costs run $2,500 a head, per year.

Eventually, Pickens wants to return all horses in government-funded holding facilities to natural habitat elsewhere after purchasing more property.

"I don't think the BLM quite grasps that our country is in a financial emergency," she said. "You can't keep spending the money they do to put horses in holding. They have a program that doesn't work, and they're trying to save face."

Last year, Pickens purchased the 14,000-acre Spruce Ranch and the adjoining 4,000-acre Warm Creek Ranch to serve as a horse sanctuary. The Elko County ranches, which she renamed the Mustang Monument preserve, come with grazing rights on roughly 564,000 acres of public land.

Abbey also criticized Pickens' media campaign supporting the sanctuary, saying some of the information requires clarification and context, and that other information is "just plain false." Pickens defended her statements.

The BLM rounds up wild horses to limit their numbers, saying it is done to protect the herds, rangelands and wildlife. Activists maintain they are being conducted to appease ranchers and make room for cows.

About 33,700 wild horses roam freely in 10 Western states, about half in Nevada. The BLM set a target level of 26,600 horses and burros in the wild, and removed 10,637 of the animals from the range in the fiscal year ending Sept. 30.

Of the $63.9 million designated for the BLM's wild horse and burro program in the last fiscal year, holding costs totaled about $37 million.

More than 40,000 horses are in government-funded holding facilities, BLM spokesman Tom Gorey said.