Barack Obama has said Mitt Romney tends to "shoot first and aim later" after his challenger in upcoming elections attacked the US president’s response to protests in North Africa.
Obama told CBS News on Wednesday that Romney’s criticisms that Obama sympathised with protesters outside US embassies were premature and proof of his rival's propensity to lash out even when he does not have his "facts right".
"There's a broader lesson to be learned here: Governor Romney seems to have a tendency to shoot first and aim later," Obama said in the interview.
"As president, one of the things I've learned is you can't do that. It's important for you to make sure that the statements that you make are backed up by the facts and that you've thought through the ramifications before you make them."
An anti-Islam film made by individuals in California, has caused uproar in several North African countries.
Protests have continued outside the US embassy in Cairo for a third day on Thursday, while an attack on Tuesday on a US consulate in the Libyan city of Benghazi resulted in the death of four US personnel, including Ambassador Christopher Stevens.
Obama's retort to Romney followed a more formal statement earlier in the day, in which he paid tribute to Stevens, promised his killers would face justice and avoided political ramifications of his killings.
On Tuesday night, Romney said it was "disgraceful that the Obama administration's first response was not to condemn attacks on our diplomatic missions, but to sympathize with those who waged the attacks".
Romney said the embassy in Cairo denounced the film on social media after the mission in Egypt was stormed, suggesting that Obama's administration had bowed to pressure from demonstrators.
But Reuters correspondents in Cairo said the embassy posted the statement on social media on Tuesday morning before the protest began, not after it had started.
A senior US official also said the statement, which condemned "the continuing efforts by misguided individuals to hurt the religious feelings of Muslims", was released before any demonstrations had begun.
The statement was later pulled from the Internet because it was not coordinated with the State Department in Washington, the official said.
On Wednesday, the Republican candidate stood by his comments and again criticized the embassy.
"The embassy in Cairo put out a statement after their grounds had been breached. Protesters were inside the grounds. They reiterated that statement after the breach. I think it is a terrible course for America to stand in apology for our values," Romney said while campaigning in Florida.
Obama's latest swipe at Romney came a week after he used the Democratic National Convention in North Carolina to portray his rival as a foreign policy novice who would usher in a new "era of blustering and blundering" abroad.
Democratic Senator John Kerry, a possible pick for secretary of state if Obama wins a second term, also fired off a scathing assault on Romney's credentials to serve as commander-in-chief.
"President Mitt Romney: three hypothetical words that mystified and alienated our allies this summer," Kerry said, referring to Romney's wobbly visit to Europe and Israel.
"For Mitt Romney, an overseas trip is what you call it when you trip all over yourself overseas. It wasn't a goodwill mission, it was a blooper reel."