Washington: Republican Mitt Romney will accuse President Barack Obama's White House of leaking classified national security information in order to gain "political advantage" in an election year.

Romney, who is challenging Obama in the November election, will deliver a key foreign policy speech in Reno, Nevada before the Veterans of Foreign Wars in which he cites complaints that Obama administration officials have divulged top-secret data that put the lives of Americans and allies at risk.

"This isn't a partisan issue; it's a national security crisis," Romney will say, according to excerpts of the speech released by his campaign.

"This conduct is contemptible. It betrays our national interest. It compromises our men and women in the field. And it demands a full and prompt investigation, with explanation and consequence," he will say.

"Whoever provided classified information to the media, seeking political advantage for the administration, must be exposed, dismissed, and punished. The time for stonewalling is over."

Republicans and Democrats alike have complained for weeks about a series of leaks which led to several explosive stories in US media, including one describing Obama's alleged push for cyber-attacks on computers that run Iran's nuclear facilities.

The Justice Department launched two criminal investigations last month after a congressional outcry over the unauthorized disclosures.

But Romney will demand even swifter action, saying it is "unacceptable" to report the findings "after election day."

Romney cites comments by Democratic Senator Dianne Feinstein, chair of the Senate Intelligence Committee, who on Monday said "I think the White House has to understand that some of this is coming from their ranks."

Feinstein said she was certain Obama himself had not disclosed the classified material, but that members of his administration did.

Last month Obama said it was "offensive" to suggest the White House would purposely release classified national security information.

But lawmakers have remained worried, and Romney's comments appear to be aimed at injecting the leaks squarely into the campaign.

"Exactly who in the White House betrayed these secrets? Did a superior authorize it? These are things that Americans are entitled to know, and they are entitled to know right now," Romney will tell the war veterans event.

"These events make the decision we face in November all the more important. What kind of White House would reveal classified material for political gain?" he will ask. "I'll tell you right now: mine won't."

(Agencies)

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