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A group of 18 foreign policy advisers to President Obama has written a public letter to Mitt Romney rebuffing criticism leveled by his campaign at Obama's national security record.

The group also offered to "engage" with Romney's team of advisers on a set of key foreign policy issues.

"Because you have repeatedly said that your foreign policies will be informed by the advice of experts, we wanted to highlight some of the factual inaccuracies in the letter from your advisers," the group wrote, referring to an open message published Tuesday in the National Review.

Romney's team, seizing on Obama's hot mic comments to Russian President Dmitry Medvedev in South Korea, accused Obama of presiding over a period of "weakness and inconstancy" and suggested it would continue if he's re-elected.

While Obama's allies offered a familiar litany of talking points to counter the claim - from progress on Iran sanctions to renewing the trade embargo with Cuba - they also turned up the heat on Romney, whose foreign policy agenda, they said, lacks substance.

"What specifically would you do to address the Iranian threat that is different from what President Obama is already doing?" they asked.

"You have said you would have left tens of thousands of U.S. forces behind in Iraq," they wrote. "Would you have done so against the wishes of the Iraqi government and people, with no legal protections?"

And, "Given the clear successes of President Obama's counterterrorism policies, why and how would you change the current approach to disrupt, dismantle, and defeat al Qaeda?"

"We are prepared to engage your advisers on these and other issues," the group said.

The letter was signed by, among others, Michele Flournoy, under secretary of defense for policy; Gen. Wesley Clark, a former NATO supreme allied commander; Richard Danzig, former Clinton administration Navy secretary and chairman of the Center for a New American Security.

See the full text of the letter and the questions, published exclusively by Foreign Policy, HERE.