FILE: Sen. John McCain, R-Ariz. (AP Photo/Jacquelyn Martin, File)

Sen. John McCain (R-Ariz.), who has alternated between working with President Obama and serving as one of his biggest antagonists, said Tuesday that the president has turned out to be worse than Jimmy Carter.

"I have never seen anything like this in my life," McCain said on KFYI-AM, while talking about Obama and the situation in Syria. "I thought Jimmy Carter was bad, but he pales in comparison to this president, in my opinion."

McCain said Syria directly affects American security because its civil war creates a haven for terrorists -- particularly on the Iraq-Syria border.

"It's becoming a regional conflict," McCain said. "It's spread to Lebanon, it's spread to Turkey, it's spread to Jordan. It is spreading throughout the region, and sooner or later, it will affect the United States of America."

Obama initially called for the use of force in Syria after the government used chemical weapons on its own people. But after Congress appeared set to deny that request, a deal was reached with the Syrian government for it to turn over its chemical weapons instead. McCain has been pushing for a more active intervention in Syria.

Republicans during the 2012 election, including Mitt Romney and Paul Ryan, attempted to liken Obama's presidency to Carter's.

(h/t Roll Call)