As he takes charge of rebuilding the Gulf Coast after the nation's most costly natural disaster, Donald E. Powell, federal coordinator of Hurricane Katrina recovery efforts, makes two points clear: Part of his job is being tough enough to say no -- and when he does so, he speaks for President Bush.

In an interview last week, for example, the former chairman of the Federal Deposit Insurance Corporation contradicted an assertion by Louisiana Gov. Kathleen Babineaux Blanco (D) that he had committed the Bush administration to local leaders' $20 billion priority, strengthening the New Orleans levee system to withstand a Category 5 hurricane instead of the current Category 3.

"He was pretty clear about it," Blanco said.

But Powell, 64, a tall, low-key Texan who wears a cattleman's belt with a lone star under his suit, demurred. "The commitment is to build the levees back to a three . . . and then to study the five."

"My accountability is to the president," he added later. "I report to the president."

A wealthy Bush backer and former banker from Amarillo, Tex., Powell acknowledged that the high points of a 30-year business career are not quite the same as the job description for facilitating reconstruction of the Gulf Coast at a cost to taxpayers of more than $100 billion.

"This job is not a chief executive," he said. "This job is more of listening . . . getting opposites together and motivating folks to do the right thing. It's being able to say yes when appropriate and being able to say no when appropriate -- and having the will to do that."

Whether Powell is the right person for that job is an urgent concern from Washington to Baton Rouge, La. To some, the conflict with Blanco illustrates the tightrope he must walk.

Appointed by an administration that initially rebuffed calls for a Katrina "czar" or "Marshall plan" for rebuilding, Powell is charged instead to help state and local leaders reach a consensus plan; bridge regional, racial and partisan divides; and persuade a debt-leery and gridlocked Washington to pay for it.

The task is enormous. Katrina destroyed perhaps 250,000 homes, prompted more than 500,000 unemployment claims and caused as much as $60 billion in insured damage and $200 billion in government losses. Powell's job is to set goals and policies for everything from restarting the New Orleans economy to rebuilding infrastructure.

Few question Powell's financial expertise or his ties to two Bush presidents, the first whose legacy he helped burnish in Texas and the current chief executive whom he helped elect. Leaders in the battered Gulf states and Congress, who praise his integrity and workhorse reputation, say they hope he has the background and management skills to complete the huge undertaking.

Sen. Mary Landrieu (D-La.) praised Powell's credentials, but added, "I also hope he brings with him a passion and sense of urgency about the need for action, versus more unfulfilled promises."

Rep. Bobby Jindal (R-La.), who has sought a Katrina coordinator for months, said he was pleased a federal recovery czar was appointed. Jindal, however, said he initially "suggested a Colin Powell, or a Jack Welch," referring to the former secretary of state and to the retired chairman of General Electric.

Democratic critics call Powell's selection business as usual by an administration they say has stocked a dysfunctional Homeland Security bureaucracy with loyalists. Even some Republicans in touch with the White House say they are pushing the president's advisers to tackle the recovery faster and more visibly. They say both Congress and the executive branch recoil at the cost and want the other to take the lead.

Yet Rep. Barney Frank (Mass.), a frequent Bush critic and top Democrat on the House Financial Services Committee, praised Powell's tenure at the FDIC.

"I found him to be very reasonable. He talks about issues and is solid on the facts," Frank said. Powell's FDIC term was scheduled to end next August.

Powell is a self-made millionaire and lifelong Baptist who extols capitalism and ethics in speeches at business schools. When the White House called about the Katrina job, Powell said, he ignored doubters and cited a duty to serve.

"Most people said, 'You don't want to do that. The likelihood of failure is much greater than success,' " he said. "What they didn't know is, that's what really motivates me."

Powell, who pauses before speaking and squints when making a point, added: "There's always going to be pricking, shoving, pushing and jibes. I'm going to ignore that. . . . I have a mission . . . and nothing is going to deter me from that."

"I've got lots to learn," he said. He mentioned receiving two books, John M. Barry's "Rising Tide: The Great Mississippi Flood of 1927 and How It Changed America" and Michael J. Hogan's "The Marshall Plan: America, Britain and the Reconstruction of Western Europe, 1947-1952."

In his statement on accepting the post and in a 45-minute interview, Powell never mentioned his new boss, Homeland Security Secretary Michael Chertoff. Powell has made a point of saying he was honored to be chosen by Bush, although Chertoff announced his appointment Nov. 1 and said Powell would report to Bush through him.

Powell employs a banker's discretion in describing his relationship with the president and his father, George H.W. Bush, whose presidential library and school Powell helped launch. An overnight guest at Camp David with his wife, Twanna, Powell said the current president is "someone I admire. . . . His values. His heart. His will to win."

Powell grew up in the working-class Palo Duro section of Amarillo. Like many ambitious young men in west Texas with little in the way of wealth or family connections, he made his first mark through high school football, becoming an all-district center in 1958, said longtime friend Stanley Marsh.

As a bank executive, he started days at 4:30 a.m. and ended only when the deal was closed, said J. Pat Hickman, chief executive of Happy State Bank in Happy, Tex. "You will not outwork him," said Hickman, who, like most people who worked with Powell in Amarillo, calls him DP. "If you produced, you were in his glow. If you didn't, you weren't his friend."

Powell rescued a troubled West Texas community bank from collapse in the late 1980s before selling it, starting another bank and selling it. He disclosed assets of $17.4 million to $58 million in 2004, according to the FDIC.

Powell's decisions in the boom-and-bust economy meant cutting jobs and foreclosing businesses, Marsh said. "He did all that, but still kept everyone's respect."

At the same time, Powell rose to prominence in GOP circles. Initially "too busy" for state politics, Powell has contributed more than $118,000 to Republican candidates and party committees since 1990, according to public records and the statement he submitted before a Senate confirmation vote in 2001.

He contributed $24,000 directly to Bush in his 1994 and 1998 bids for Texas governor and 2000 presidential race. Powell was an original member of Bush's 2000 fundraising committee and raised more than $100,000 as a "Pioneer." In 1995, Bush appointed Powell to the Texas A&M board of regents.

The university attracted the presidential library and museum of former president Bush, and started the Bush School of Government and Public Service. Powell chairs the school's advisory board, serving at times with Vice President Cheney's wife, Lynne; Secretary of State Condoleezza Rice; and presidential son and brother Neil Bush.

"Don has an extraordinary ability to get varied, disparate people to work together, and it's a combination of persuasion and also toughness," said Robert M. Gates, Texas A&M president since 2002 and CIA director under the first President Bush. "The job is going to get done -- and it will get done a lot easier if everybody works together."

Researcher Meg Smith contributed to this report.

Donald E. Powell was FDIC chairman when the president made him federal coordinator of the rebuilding effort.