Former presidential candidate Rick Santorum endorsed Mitt Romney in an email to supporters, after meeting Romney what Santorum called a “productive” conversation about policy issues and their past disagreements.

“Above all else, we both agree that President Obama must be defeated,” Santorum wrote. “The task will not be easy. It will require all hands on deck if our nominee is to be victorious. Governor Romney will be that nominee and he has my endorsement and support to win this the most critical election of our lifetime.”