John Kerry raised eyebrows Sunday following comments, caught on an open mic, that left some wondering whether he was criticizing Israeli assurances that its ground offensive in Gaza would be limited.

Kerry's comments occurred between multiple television interviews. He was heard in a phone conversation with a State Department deputy, Jonathan Finer, discussing the deaths of Israeli soldiers killed overnight.

"I hope they don't think that's an invitation to go do more," Kerry said in the unguarded moment. "That better be the warning to them."