Attempting to build late momentum behind his bid for the White House, Mr Romney will use a speech on foreign policy to promise “peace through strength” and condemn Mr Obama for relegating the US to “leading from behind” overseas.
"The attacks on America last month should not be seen as random acts," he was due to say later today. "They are expressions of a larger struggle that is playing out across the broader Middle East—a region that is now in the midst of the most profound upheaval in a century. And the fault lines of this struggle can be seen clearly in Benghazi itself."
"The attack on our consulate in Benghazi on September 11, 2012, was likely the work of the same forces that attacked our homeland on September 11, 2001. This latest assault cannot be blamed on a reprehensible video insulting Islam, despite the administration’s attempts to convince us of that for so long.
"No, as the administration has finally conceded, these attacks were the deliberate work of terrorists who use violence to impose their dark ideology on others, especially women and girls; who are fighting to control much of the Middle East today; and who seek to wage perpetual war on the West."
"I will work with our partners to identify and organise those members of the opposition who share our values and ensure they obtain the arms they need to defeat Assad’s tanks, helicopters, and fighter jets," his prepared text says.
Mr Romney was also due to say that he would put Iran "on notice" and that the US and their allies "will prevent them from acquiring nuclear-weapons capability".
He was also due to pledge his backing for a two state solution in the Middle East, calling for "a democratic, prosperous Palestinian state living side by side in peace and security" with Israel. Last month, Mr Romney was caught out with a leaked video, in which he said the Palestinians "have no interest whatsoever in establishing peace".
The former Massachusetts governor claims that Mr Obama has damaged ties with key US allies such as Israel, while showing weakness towards Iran and Russia and mishandling the Arab Spring.
The Obama administration has come under mounting pressure over the past four weeks for changing its account of the attack on its Benghazi consulate, and concluding only later that it had been a planned strike by extremists.
Asked if Mr Romney would accuse Mr Obama of misleading voters, Richard Williamson, an adviser and former US envoy to Sudan, said: “He's been clear that part of the responsibility of the President of the United States and the leaders of our government is transparency. Clearly they failed that test with respect to the events in Benghazi.”
Early indications are that his poll ratings were boosted. Mr Obama's average national lead has dropped from 3.1 percentage points on the day of the debate to 1.4, according to RealClearPolitics.
Mr Obama's advantage in Wisconsin, one of 10 key battleground states, has tightened from seven points a fortnight ago to just two points, according to PPP, a Left-leaning pollster.
The President's team yesterday stepped up efforts to claim Mr Romney had distorted his budget plans to appear more moderate. Robert Gibbs, an adviser, said Mr Romney had done a “superb acting job”.
Michael Nutter, the Mayor of Philadelphia, told CNN: “If you just lay out lie after lie after lie about your own plan as well as what the President has been talking about, of course you can look good”.
Mr Obama's prospects were, however, boosted by new data on Friday showing that the unemployment rate had dipped below eight per cent for the first time in than three and a half years.
Pressure will later this week fall on Joe Biden, Mr Obama's gaffe-prone deputy, to settle Democratic nerves by delivering a stronger performance against Paul Ryan in the campaign's sole vice-presidential debate, which will be held in Danville, Kentucky, on Thursday.
Jon Swaine, Telegraph.co.uk