Mitt Romney - who famously clashed with President Obama on U.S.-Russia relations three years ago - spoke today at a forum in Washington, saying Obama's foreign policy "has been a disaster."

FLASHBACK: Obama Mocks Romney for His Concerns About Putin, Russia

Earlier today, Russia commenced airstrikes in northern Syria in support of the Assad regime and asked that American fighter jets stop flying in the area. 

Romney spoke at the Washington Ideas Forum today in his first public comments since an interview in June on The Kelly File.

Romney said the president could have dealt with this three years ago, but now the options are limited. Romney said Obama repeatedly "paints himself into a corner" by failing to act.  

In a 2012 presidential debate, Romney faced off with the president over the threat posed by Russia, calling the Kremlin a top "geopolitical foe" of the U.S.

Obama fired back that Romney's views were outdated, joking that, "the 1980s are calling to ask for their foreign policy back."

Romney also said today that he does not believe Donald Trump will be the Republican nominee in 2016, calling Trump's strategy on ISIS "absurd and dangerous."

"I don't think that kind of proposal is likely to lead him to become our nominee," said Romney.

Trump told Bill O'Reilly he believes it's a "wonderful thing" that Russia is going after ISIS. 

"If he wants to fight ISIS, let him fight ISIS. Why do we always have to do everything?" Trump asked.

The airstrikes unleashed by Russia, however, are targeting other Syrian opposition forces, not ISIS, Jennifer Griffin reported this morning. 

Watch the comments in John Roberts' report above.