Obama: McCain will 'endanger' US

Polls suggest Mr Obama is ahead of his Republican rival

US Democratic presidential hopeful Barack Obama has warned that rival John McCain would "endanger" US security.

He said that the election winner would face security "tests", due in part to President George Bush's "bad policies".

His running-mate, Joe Biden, said at the weekend that Mr Obama could face a "generated international crisis" within six months of becoming president.

Mr McCain, the Republican candidate, said Mr Biden's remarks proved Mr Obama would be a risky presidential choice.

Opinion polls indicate that Mr Obama is leading Mr McCain with less than two weeks to go before the 4 November election.

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A Reuters/C-SPAN/Zogby poll released on Thursday gives Mr Obama a 12-point lead over Mr McCain, with 52% to his 40%.

An NBC/Wall Street Journal poll puts Mr Obama on 52%, 10 points ahead of Mr McCain, while a Gallup tracking poll has the Democrat ahead by eight points, with 52% to Mr McCain's 44%.

However, an AP-GfK poll released on Wednesday suggests a much narrower margin, putting Mr Obama only one point ahead, with 44% support to his rival's 43%.

Clear signal

Responding to attacks over Mr Biden's comment on the likelihood that he would be "tested" by an international crisis, Mr Obama said his running-mate "sometimes engages in rhetorical flourishes".

"His core point was, the next administration is going to be tested regardless of who it is," he told reporters.

"The question is: Will the next president meet that test by moving America in a new direction, by sending a clear signal to the rest of the world that we are no longer about bluster and unilateralism and ideology?"

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Mr Obama also accused John McCain of wanting to continue "the policies that have put our economy into crisis and endangered our national security".

The McCain camp rejected Mr Obama's explanation, and accused him of lacking leadership.

"Joe Biden guaranteed a generated international crisis if Barack Obama is elected, and a smile-for-the-cameras press conference isn't going to mitigate the risk of an Obama presidency," said McCain spokesman Tucker Bounds.

Mr Obama was speaking at a news conference following a round-table meeting with foreign policy experts to discuss the "urgent issues" facing the world.

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He also addressed criticisms from the McCain campaign that his tax plans amounted to "socialism".

"Was John McCain a socialist back in 2000?" he said, referring to Mr McCain's earlier opposition to President Bush's tax-cutting plans.

And at a rally later in the day, he poured scorn on Mr McCain's accusation that Mr Obama would raise taxes for Americans like Joe Wurzelbacher, the plumber who gained prominence after being mentioned numerous times in the last presidential debate.

"Let's be clear who John McCain is fighting for - he's not fighting for Joe the Plumber, he's fighting for Joe the Hedge Fund Manager."