Secretary of State John Kerry doubled down Tuesday in refusing to accept any blame for the Obama administration refusing to enforce the red line set by President Obama for the use of chemical weapons in Syria.

While speaking with PBS' Judy Woodruff at the U.S. Institute of Peace, Kerry blamed Congress, the United Kingdom, and a "perception" of what Obama had said and done for the U.S. not intervening after Syrian President Bashar al-Assad used chemical weapons on his own people.

"President Obama never retreated from his red line," Kerry said. "He never changed his mind about his readiness to bomb Assad to make it clear you don't use chemical weapons. Never!"

Kerry then mentioned former British Prime Minister David Cameron requesting permission at the time to use military force in Syria and the Obama administration wanting Congress to grant the president the authority to use force. Under the War Powers Act, Obama could act for up to 60 days without congressional approval.

Kerry touted a deal made with Russia and the Syrian regime to have Assad remove his chemical weapons stockpile. Despite the deal, the Assad regime continued to use chlorine gas in Syria years after the deal was brokered.

"I will readily acknowledge that this notion that the president didn't follow through took hold and it has cost us, and I acknowledge, yes, it became a perception that became a sort of diplomatic reality," Kerry said. "It fed this notion that the administration wasn't there to support its ally, but it's just not accurate.

Kerry and Woodruff were speaking at a conference on the transition process to the incoming Trump administration.