Democrat Barack Obama accused President George W Bush of "fear-mongering" for suggesting Democrats wanted to appease terrorists and vowed to meet leaders of hostile nations like Iran if elected.

In a long-distance foreign policy debate that ricocheted through the US presidential campaign, Republican candidate John McCain called Mr Obama reckless and out of touch with reality, while Hillary Clinton has defended her rival Democrat.

Mr Obama clearly relished the clash with Mr Bush and chance to link Mr McCain with the unpopular Republican president.

He says Mr Bush had contributed to Iran's rise in the Middle East by launching the Iraq war, which he says had removed Baghdad as a counterweight to the Islamic republic.

The Illinois senator said Mr McCain was as much to blame as Mr Bush for what he termed a US Middle East policy failure.

"They're trying to fool you, and trying to scare you, and they're not telling the truth. And the reason is because they can't win a foreign-policy debate on the merits. But it's not going to work," says Mr Obama, the Democratic front-runner vying to face McCain in the November presidential election.

'direct talks'

Mr Obama says if elected president he would meet, with preparation but without preconditions, leaders Mr Bush has avoided, such as Iranian President Mahmoud Ahmadinejad, Syrian President Bashar al-Assad, North Korea's Kim Jong-il and Venezuelan President Hugo Chavez.

"I would engage in direct talks," he told reporters after a speech.

Iran, Syria and North Korea are considered by the US State Department to be state sponsors of terrorism while Venezuela has stoked anti-American sentiment in South America.

'comfort of appeasement'

Mr Bush triggered Democratic outrage on Thursday by saying in a speech in Israel that some politicians would pursue the "false comfort of appeasement" by negotiating with militant groups such as the Palestinian Hamas and Hezbollah organisations and Iran.

Mr Obama says Mr Bush and Mr McCain were guilty of "bombast, exaggerations and fear-mongering."

The White House says it was baffled at the Democratic response and that Mr Bush had long made similar statements.

"I would encourage you to ask them what sentences that they disagree with, what specific sentence," White House counsellor Ed Gillespie said on the Air Force One flight to Saudi Arabia.

Mr McCain's campaign accused Mr Obama of an "hysterical diatribe" and the Arizona senator said he welcomed a debate on security.

"Talking, not even with soaring rhetoric, ... will not convince Iran to give up its nuclear program. It is reckless to suggest that unconditional meetings will advance our interests," Mr McCain told a Tennessee meeting of the National Rifle Association.

It was wrong to believe there were no enemies in the world, he said. "Until Senator Obama understands that reality, the American people have every reason to doubt whether he has the strength, judgment and determination to keep us safe."

The episode allowed Mr Obama to talk directly to Mr Bush and elevate himself on the national stage as he tries to wrap up the Democratic presidential nomination. Even party rival Hillary Clinton has come to Obama's defense, saying on Thursday that Mr Bush's remarks were "outrageous and deeply offensive."

Weakened by the Iraq war and ailing economy, Republicans hope to convince Americans that Mr Obama is too inexperienced to be trusted as commander in chief, as Mr McCain tried to assert on Friday.

But Mr Obama sought to turn the experience question around on Mr Bush and Mr McCain.

"They've got to answer for the fact that Iran is the greatest strategic beneficiary of our invasion of Iraq. It made Iran stronger, George Bush's policies," he says.

"They're going to have to explain why Hamas now controls Gaza, Hamas that was strengthened because the United States insisted that we should have democratic elections in the Palestinian Authority," he added.