The Lead with Jake Tapper

Exclusive: Mitt Romney on Syria policy 'vacillation': It was not the president's finest hour

Watch CNN at 6 p.m. ET for more of our interview on foreign policy with Mitt Romney.

President Barack Obama was criticized, by both Republicans and Democrats, on his approach to Syria. The president threatened to use force against the regime, then decided to seek Congressional approval to authorize a military strike, and then he asked Congress to delay the vote.

"I think it was not the president's finest hour," said former Republican presidential candidate Mitt Romney. "He looked like he hadn't thought it through and hadn't considered the right course in advance."

"The President of the United States as he plans what action he thinks is appropriate needs to think through all the options from the very beginning, settle on the one he considers to be the most effective, and then communicate that aggressively with whatever audience he thinks needs to hear it.

"And that was not done; it was not done with our friends in Great Britain. It was not done here. And there was vacillation here," said Romney.