US President Barack Obama hit out at his Republican foe Mitt Romney on Iraq Tuesday, warning that America did not need a another president who started wars with no plan to end them.

Obama pounced on Romney's complaint in a major foreign policy speech on Monday that the president had failed to secure Iraqi agreement for a residual US troop presence after the withdrawal of troops last year.

"Governor Romney said it was tragic to end the war in Iraq. I disagree. I think bringing our troops home to their families was the right thing to do," Obama told a 15,000-strong crowd in Columbus, Ohio.

If he'd gotten his way, those troops would still be there. In his speech yesterday, he doubled down on that belief. He said ending that war was a mistake."

"Ohio, you can't turn a page on the failed policies of the past if you're promising to repeat them.

"We cannot afford to go back to a foreign policy that gets us into wars with no plan to end them. We're moving forward, not going back."

Obama made his name on his early opposition of the Iraq war, when he was a lowly state lawmaker in Illinois, and he promised as part of his 2008 presidential campaign to get all US troops home.

He is promising to end the Afghan war in the same "responsible" way as he said he ended the Iraq war.

Republican critics, however, have argued that the failure of the administration to secure agreement for a small US force in Iraq cost America influence in Baghdad and contributed to current instability in the country.

Romney also accuses Obama of using political calculations to manage the withdrawal of US troops from Afghanistan, though says he would also mandate the pullout of all combat soldiers by 2014, as Obama has proposed.

The Republican candidate said on Monday that "America's ability to influence events for the better in Iraq has been undermined by the abrupt withdrawal of our entire troop presence."

In an earlier comments in November 2011, Romney said the withdrawal of US troops from Iraq was "tragic."