NEW YORK — President Bush yesterday accepted blame for the sluggish federal response to Hurricane Katrina — 15 days after the monstrous storm struck the Gulf Coast, killing at least hundreds.

"Katrina exposed serious problems in our response capability at all levels of government, and to the extent that the federal government didn't fully do its job right, I take responsibility," Bush said in a rare admission of failure during his nearly five years as president.

He accepted what he parsed as his share of the blame during a White House news conference called to confront another weight of his presidency — the Iraq war — and flew to New York for talks at the United Nations.

"I can do more than one thing at one time," Bush assured a reporter in Mississippi on Monday, who asked about his heavy foreign-policy schedule this week.

But it's been a struggle for the White House, particularly with the Katrina recovery efforts.

Facing new lows in the public-opinion polls, Bush has sought not only to ramp up federal relief efforts but also to shore up his standing.

He will return to the stricken region tomorrow for his fourth tour and plans to address the nation in prime time. But he had been slow to cut short his vacation last month after the hurricane hit. And his administration has been roundly criticized for being ill-prepared for the magnitude of the disaster.

Much of the harshest criticism had been directed at Michael Brown, director of the Federal Emergency Management Agency (FEMA), who was recalled from the disaster area Friday and resigned Monday. Bush had praised his efforts early on, declaring: "Brownie, you're doing a heck of a job."

"I want to know what went right and what went wrong. I want to know how to better cooperate with state and local government," Bush said yesterday, as he accepted blame.

Sen. Mary Landrieu, D-La., who has criticized the federal response, later said she was ready to move on.

"The president's comments today will do more to move our country forward from this tragedy than anything that has been said by any leader in the past two weeks," she said.

Critics often have criticized Bush for a perceived inability to admit mistakes. In perhaps the most famous example, he refused to name one last fall when a participant asked for one during one of the president's debates against Democratic challenger John Kerry.

Stephen Hess, professor of media and public affairs at The George Washington University, noted that presidents historically have been reticent to acknowledge errors.

"This is not a full-fledged mea culpa. But by presidential standards, it's there, or pretty close to it," Hess said. "The government did screw up, and he is president of the United States."

Bush was pressed about the federal disaster response during a joint news conference in the White House with Iraqi President Jalal Talabani. Both men pledged to stay the course in Iraq, and neither committed to a timetable for drawing down U.S. forces.

"We will not waver," Bush said bluntly. And he made clear again during his tour of the Gulf Coast on Monday that the United States had enough military personnel for both Iraq and hurricane relief.

Bush's acceptance of responsibility for the federal response was his first, after days of finger-pointing among state, local and federal officials.

A new Washington Post-ABC News poll found that two of the president's strengths — his leadership and his trustworthiness in a crisis — have been eroded by the chaos after the Hurricane Katrina.

Background on the Bush-Kerry debate was provided by Seattle Times archives.