(CNN) - Sen. John Kerry fired back Wednesday at former Sen. Rick Santorum's strong opposition to a U.N. treaty promoting the rights of the disabled that failed in the Senate this week.
"Rick Santorum was just not factual," Kerry said on CNN's "The Situation Room."
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"Now what he did was he gave some people here an excuse to hide behind ... when they know that there are people who hate the United Nations, who don't want any United Nations treaty, and so they gave them a reason to be able to say, ‘this is why I'm voting against it,’" Kerry said.
Republicans in the Senate blocked ratification on Tuesday of the U.N. Convention on the Rights of Persons with Disabilities. Former Senate Majority Leader Bob Dole appeared on the floor of the Senate in a last-minute effort to draw GOP support.
One of Santorum’s daughters, Bella, was born in 2008 with the rare genetic disorder Trisomy 18. He represented the Keystone State in the U.S. Senate from 1995 to 2007 and sought the Republican presidential nomination this year.
Santorum outlined his opposition to the treaty most recently in an opinion piece published in the Daily Beast on Wednesday. He wrote that the treaty "gives too much power to the U.N., and the unelected, unaccountable committee tasked with overseeing its implementation, while taking power and responsibility away from our elected representatives and, more important, from parents and caregivers of disabled persons."
He wrote further that “our nation has been the worldwide leader when it comes to protecting the disabled. We should be telling the U.N., not the other way around, how to ensure dignity and respect for the disabled."
Kerry was animated in his response, charging Santorum did not know what he was talking about.
"He either simply hasn’t read the treaty or doesn't understand it or he was just not factual in what he said," Kerry said, "because the United Nations has absolutely zero, zero, I mean zero ability to order or to tell or to even - I mean they can suggest - but they have no legal capacity to tell the United States to do anything under this treaty. Nothing.”
Kerry pointed out that the treaty was negotiated under Republican President George Herbert Walker Bush and signed at the United Nations by his son, Republican President George W. Bush.
Supporters of the treaty include key Republicans like Sen. John McCain.