"This administration has proven stunningly ineffective in diplomacy," Kerry told NBC television. "Our administration has been as arrogant and ineffective as it could possibly be."

"If I am president I will not only personally go to the UN (after election) I will go to other capitals and I will have my secretary of state fully empowered ... which we now know from Bob Woodward's book is not the case," Kerry said.

Journalist Woodward's new book, "Plan of Attack" says Secretary of State Colin Powell was effectively sidelined in decision-making before the invasion of Iraq.

National security adviser Condoleezza Rice meanwhile confirmed the latest account of Bush's prewar planning in the book saying the president asked Defense Secretary Donald Rumsfeld for military options in Iraq as early as November 2001, at a time when officials in Washington publicly said they were seeking a diplomatic way out of the standoff over suspected nuclear, biological and chemical weapons.

"The president apparently did talk to Don Rumsfeld and say to him, you know, 'I need to know what my options might be concerning Iraq'," Rice told Fox news.

"We planned for Afghanistan, we fought the war in Afghanistan. By the end of November, things started to wind down in Afghanistan, and I do think the president's mind was beginning to move to what else he would have to do to deal with the blow, with the threat that had emerged as a result of 9/11."

Kerry insisted "this administration misled America. Nothing is more important than how a president takes a nation to war, how a president decides to put young men and women at risk for our nation."

"I believe this president broke faith with the rules of how a president does that. He even broke faith with his own promises to the country."

What's more, "never has the United States of America been held in such low regard, and polls have shown this."

Kerry said that if elected "I will immediately reach out to other" countries and go to the United Nations and seek to reintegrate the United States into the international community. He promised change in "our approach to North Korea", AIDS, nonproliferation and global warming.

"I will never cede the security of the United States to any institution ... that said, I will be a president who understands that multilateralism is not weakness it is strength. (Bush's) father (ex-president George Bush) did a brilliant job of that."

Asked if the US-led war in Iraq was a mistake, Kerry said, "I think the way the president went to war was a mistake.

"Iraq had nothing to do with al-Qaeda. ... We need to take a look at the truth again.

"You cannot bring other nations to the table through the back door. You cannot have America run the occupation (in Iraq), make all the reconstruction decisions, make the decisions of the kind of government that will emerge and pretend to bring other nations to the table."

Asked if he would be comfortable with a regime like Iran's in Iraq, Kerry said "I think what is important is that it have some kind of pluralistic representation ... what is critical is a stable Iraq.

"What we need is a diplomacy that is ongoing and engaged with the Arab community" to help facilitate a settlement in the Israeli-Palestinian conflict, he said.

Asked about Cuba, the only communist country in the Americas on which the United States has had a trade embargo for more than 40 years, Kerry said "I have never suggested lifting the embargo ... but for anybody who suggests that what we are doing has worked," he would suggest otherwise.

Kerry said he would consider a new approach encouraging travel by US citizens to Cuba. On ending sanctions, he said "I wouldn't just go and give something for nothing. I would like to see what we can negotiate" with Cuban Americans in terms of new approaches.

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