WASHINGTON -- Japan is quibbling about paying the United States all of the $10.7 billion it pledged for the costs of the Persian Gulf war, administration officials told Congress yesterday.

"They have a different interpretation of the commitment, and we're trying to clear up the misunderstanding," Deputy Assistant Secretary of State Richard Hecklinger told the House Budget Committee.

But David Mulford, a senior Treasury official who appeared before the House Foreign Affairs Committee a day earlier, was less diplomatic.

Mr. Mulford called Japan "the most delinquent" ally and said it is holding up about $1.2 billion.

Despite the haggling with Japan, administration officials assured Congress that the effort to get allies to pay for Operation Desert Storm has been nearly as successful as the war itself and that the allies will pick up at least three-fourths of the war's cost.

"The overall picture is really pretty impressive," Mr. Hecklinger said.

Pentagon Comptroller Sean O'Keefe told the Budget Committee that the allies have paid $37 billion out of their $54.6 billion in pledges to cover U.S. costs.

Officials said they expect to collect the rest by the end of the year.

The final cost of the war is not known yet, but estimates put it in the $60 billion to $70 billion range. That should keep the cost to taxpayers within the $15 billion Congress has already set aside.