WASHINGTON — Two top Marine Corps officers acknowledged yesterday that they waited two months to issue a contract for armor kits to protect the undersides of Humvees after promising to do so earlier this year.

Testifying before the House Armed Services Committee, Gen. William Nyland, the assistant commandant of the Marine Corps, and Brig. Gen. William Catto, the chief of Marine Corps Systems Command, attributed the delay to a "lack of leadership." They assured the committee that all Humvees and military trucks that the Marines used in Iraq would be adequately protected by December.

Lawmakers expressed frustration yesterday that troops don't have enough protective armor and other equipment to protect them from homemade bombs, which typically are made from castoff artillery shells and other munitions.

"This is a sad day for us," said Rep. Duncan Hunter, R-Calif., the committee's chairman and the father of a Marine who served in Iraq.

Catto, who has oversight of all Marine Corps equipment issues, took the blame for the delay. "This is a lack of leadership on my part for not paying more attention to that specific contract," he said. Nyland also accepted fault but said increased production of armor kits in the United States had made up for the shortfall.

"I acknowledge that we took our eye off the ball on that contract," he said. "But we had a parallel course at the same time ... and we have in fact now almost 400 underbodies on the ground for the purposes of installation at the unit level."

At least 34 Marines have died from so-called-improvised explosive devices in Iraq this year, according to Iraq Coalition Casualty Count, a Web site that tracks and classifies casualties based on Defense Department news releases. Overall, 155 U.S. military deaths have been attributed to such bombs this year, more than half of U.S. combat fatalities.

The Marines aren't the only military branch that has experienced delays in protecting vehicles. The Philadelphia Inquirer reported in April that the Army said all of its 35,000 vehicles in Iraq, including Humvees, had some sort of armor, but 11,700 were protected with nothing more than crudely cut sheets of steel that didn't meet Army standards. The Army is replacing that armor, but the Pentagon said the job wouldn't be done until September.

Hunter said conversations about providing more armor for Marine Humvees began earlier this year, after a Marine sergeant came up with a way of using scrap steel to fashion plates to protect the undersides of Humvees. After initial discussions with Defense Department officials in February went nowhere, Hunter met in April with Nyland, who agreed that steel in Kuwait could be used to produce 650 protective kits, Hunter said. A contract to produce those kits wasn't signed until Monday, however.

Nyland and Catto said technical issues involving the quality of the steel in Kuwait had initially delayed the project and that production of armor kits was stepped up in the United States.

Nyland said efforts were under way to ensure that almost 2,000 Humvees and trucks had the necessary protective armor kits by December.