Washington (CNN) A U.S. military campaign against Iran's nuclear facilities would only take "several days" of bombing, Sen. Tom Cotton said Tuesday.

Cotton, the Arkansas Republican freshman who has emerged as a leading critic of President Barack Obama's effort to strike a deal to thwart Iran's nuclear ambitions, told the Family Research Council's Washington Watch radio that Obama's assertion that the alternative to the pact is war is a "false choice."

"This president has a bad habit of accusing other people of making false choices, but he presented the ultimate false choice last week when he said it's either this deal or war," he said in comments first noted by BuzzFeed News.

"He's the one that said for years no deal is better than a bad deal, but he seems to have repudiated that position," Cotton said.

Cotton, a U.S. Army veteran, was the lead author of a now-infamous letter warning Iran that Congress could abandon the deal once Obama leaves office. It was signed by 47 Republicans, infuriating the White House.

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