By Charles Abbott

WASHINGTON (Reuters) - Although federal budget cuts are scheduled for March 1, it could be months before a threatened shutdown of U.S. meat plants would occur because of a furlough of meat inspectors, U.S. Agriculture Secretary Tom Vilsack said on Thursday.

Vilsack said work rules vary for USDA employees, who get from 30 to as many as 120 days, or four months, notice of impending layoffs.

"I'm not sure what it is in the food safety area," Vilsack told reporters at the annual USDA Agricultural Outlook Forum after warning that a two-week furlough of all inspectors may be unavoidable.

USDA has raised the prospect of the furlough repeatedly in the past two weeks as $85 billion in federal budget cuts loom unless Democrats and Republicans can come up with an alternative to the automatic cuts agreed to in 2011.

Meatpackers and processors cannot ship their products across state lines without the USDA inspection seal, so a furlough would force them to halt operations. They would lose an estimated $10 billion in production, according to the USDA.

Americans could see higher prices and a temporary shortage of chicken breasts, pork chops, chuck roast, hot dogs and other meats in grocery stores, carry-out stands and restaurants.

The USDA has declined to discuss the timing of furloughs, which could affect up to one-third of its 100,000 employees.

Meat inspectors may qualify for 30 days' notice, said an industry source. A spokesman for the union representing inspectors was not immediately available for comment.

During a speech to the USDA conference, Vilsack said the meat inspector furlough was "a risk we now face."

"This is a direct prescription from Congress to reduce every line item," said Vilsack. Afterward, he told reporters that he could not shift money to cover the cost of inspectors nor could he exempt the meat inspection agency from cuts. Continued...