U.S. Foodservice Inc., the Columbia firm beset by accounting problems and government investigations, yesterday took a first public step toward defending itself, blaming its troubles on "a few trusted employees" who "let our company down."

In an attempt to distance himself from the scandal, James L. Miller, the company's chief executive, pointed a finger at his subordinates and the company's accounting firm. He sent a letter to the firm's biggest customers yesterday, seeking to reassure them about the future of the nation's second-largest food wholesaler. U.S. Foodservice's corporate parent, Royal Ahold NV, a large Dutch food company that also owns Giant Food Inc., last week announced that it will restate earnings by at least $500 million for the past two years.

In his letter, Miller took pains to say the departures of Ahold's chief executive and chief financial officer last week had "nothing to do with our company. Their resignations are the result of events that occurred outside the United States," Miller wrote. A spokesman for Ahold declined to comment. In its statement last week announcing it had ousted its chief executive Cees van der Hoeven and Chief Financial Officer Michiel Meurs, Ahold disclosed "significant accounting irregularities" at U.S. Foodservice.

Miller, who has been at U.S. Foodservice's helm since 1989, also used his letter to point a finger at Deloitte Touche Tohmatsu, which has audited Ahold's books for several years.

"Throughout its service to our company, Deloitte & Touche's auditors repeatedly assured me and other senior managers that our accounts were in proper order," Miller wrote. "Sadly, those assurances turned out not to be true."

A spokesman for the accounting giant declined to comment. Deloitte previously said it uncovered problems that caused it to put its 2002 audit of Ahold on hold. Deloitte also has pulled its audit opinions for 2000 and 2001.

Miller also told customers that "key senior managers" would remain and that "we are a profitable company and expect to remain that way."

The U.S. attorney's office in Manhattan and the Securities and Exchange Commission are investigating the accounting irregularities. Lawrence Byrne, a partner at White & Case, was hired by Ahold to conduct its own probe.

U.S. Foodservice suspended Mark P. Kaiser, its chief marketing officer, and Tim Lee, a purchasing executive, last week.

"My client has thus far cooperated with the company's investigation," said Richard Morvillo, a lawyer for Kaiser. "We feel confident once all the facts are known he will be vindicated."

Lee could not be reached for comment yesterday.

Separately, one credit-reporting service said yesterday that a major company that insures "accounts receivable" has canceled coverage to suppliers who provide food to U.S. Foodservice. That means if U.S. Foodservice does not pay the money it owes to those suppliers, the insurance company will not pick up the cost, said Beth Gideon, who heads the special investigations department at Seafax, a credit-reporting service in Portland, Maine. Seafax declined to name the insurance company that canceled coverage, a development first reported by Dow Jones News Service.

"It means suppliers are on their own," Gideon said. "They don't have insurance against that exposure."

She does not expect many suppliers who lost coverage to sever ties with US Foodservice, but she said the news could add to the overall jitters about the company. A spokeswoman for U.S. Foodservice declined to say whether the coverage had been canceled. She said the company remains a profitable, key player in the industry and that it will meet its financial obligations.

In announcing it had ousted its chief executive, Cees van der Hoeven, Royal Ahold cited "significant accounting irregularities" at U.S. Foodservice.