Washington: With just 15 days to go for the US presidential poll, Republican President George W Bush's former secretary of state Colin L Powell on Sunday endorsed Democratic nominee Barack Obama, calling him a "transformational figure".
"He has both style and substance," said Powell, a Republican and retired General, speaking on NBC's "Meet the Press".
Obama "has displayed a steadiness; showed intellectual vigor. He has a definitive way of doing business that will do us well", he added.
"I think he is a transformational figure, he is a new generation coming onto the world stage, onto the American stage, and for that reason I'll be voting for Sen. Barack Obama," said Powell, the highest profile Republican to add his support to Obama.
Powell, who served as secretary of state under Bush from 2001 to 2005, was once seen as a possible presidential candidate himself.
In offering his endorsement for Obama, Powell cited the Democrat's "ability to inspire" and the "inclusive nature of his campaign", while questioning rival Republican candidate John McCain's decision to chose Alaska Governor Sarah Palin as his vice presidential running mate. Powell said he did not believe Palin was ready to become president.
Expressing concern about what he characterised as a recent negative turn of McCain's campaign, he said he was disappointed by their decision to seek to tie Obama to William Ayers, a former radical who violently protested the Vietnam War in the 1960s.
"I think that's inappropriate. I understand what politics is about - I know how you can go after one another, and that's good. But I think this goes too far, and I think it has made the McCain campaign look a little narrow. It's not what the American people are looking for," he said.
While Powell and Obama have spoken occasionally, including a face-to-face meeting earlier this year, the endorsement caught the Democratic presidential nominee by surprise. Aides said it was not yet known whether he and Obama would campaign together - or what Powell would do alone - in the final two weeks of the presidential campaign.
Later, answering reporters' questions outside NBC's Washington studio, Powell said: "I think that Senator Obama brings a fresh set of eyes, fresh set of ideas to the table.
"I think that Senator McCain, as gifted as he is, is essentially going to execute the Republican agenda, the orthodoxy of the Republican agenda with a new face and a maverick approach to it, and he'd be quite good at it, but I think we need more than that."
Powell said he has some concerns about the direction of the Republican Party, adding that it has "moved more to the right than I would like to see it".
In regard to the financial crisis, which Powell called the candidates' "final exam", Powell said McCain appeared unsteady in dealing with it, while Obama had excelled in handling the situation.
"Obama displayed a steadiness, an intellectual curiosity, a depth of knowledge," Powell said. "He has met the standard of being a successful president, being an exceptional president," he said.
During the campaign, Powell has met both candidates and said he has a lot of respect for McCain. He said Sunday that he thinks both candidates are qualified to be president.
Speaking on Fox News Sunday, McCain said he respects and admires Powell, and the announcement "doesn't come as a surprise".
"I'm also very pleased to have the endorsement of four former secretaries of state -Secretaries [Henry] Kissinger, [James] Baker, [Lawrence] Eagleburger, and [Alexander] Haig - and I'm proud to have the endorsement of well over 200 retired army generals and admirals," McCain said.