WASHINGTON — Former Secretary of State Colin Powell endorsed Democrat Barack Obama for president today, describing the Illinois senator as a "transformational figure."

Powell said both Obama and Republican John McCain are qualified to be commander in chief. But he said Obama is better suited to handle the nation's economic problems as well as help improve its standing in the world.

"It isn't easy for me to disappoint Sen. McCain in the way that I have this morning, and I regret that," Powell said on NBC's "Meet the Press."

"But I firmly believe that at this point in America's history, we need a president that will not just continue, even with a new face and with the changes and with some maverick aspects, who will not just continue basically the policies that we have been following in recent years," Powell said.

"I think we need a transformational figure. I think we need a president who is a generational change and that's why I'm supporting Barack Obama, not out of any lack of respect or admiration for Sen. John McCain."

Powell's endorsement has been much anticipated because he is a Republican with impressive foreign policy credentials. At the same time, he is a black man and Obama would be the nation's first black president.

Powell said he was cognizant of the racial aspect of his endorsement, but said that was not the dominant factor in his decision. If it was, he said, he would have made the endorsement months ago.

Powell served as secretary of state in President Bush's first term, and helped make the case before the United Nations for the U.S.-led invasion of Iraq in March 2003. A retired general, Powell also was the nation's top military commander, chairman of the Joint Chiefs of Staff, during the first Gulf war under President George H.W. Bush.

McCain said he disagreed that Obama is qualified to be president.

"We have a respectful disagreement," McCain, interviewed on "Fox News Sunday," said of Powell.

Powell said McCain has been a good friend for 25 years. But Powell expressed disappointment in the negative tone of McCain's campaign, as well as in his choice of Alaska Gov. Sarah Palin as the Republican vice presidential nominee.

"I don't believe she's ready to be president of the United States," Powell said.

Powell said he does not plan to campaign for Obama.