Iran us nuclear talks

Senator Tom Cotton tells the 'Atlantic,' "I think if we choose to go down the path of this deal, it is likely that we could be facing nuclear war."

Jewish officials raise concerns about deal with Obama administration officials.

"It may be that the deceptive other side wants to restrict us in the details," Iranian leader says.

“The biggest threat to our security and future was and remains Iran's attempt to arm with nuclear weapons,” he said. “The agreement being put together at Lausanne is paving the way for that result.”

Diplomat quoted by Chinese news agency Xinhua as saying the atmosphere on Monday has turned from "optimism" to "gloom" among negotiators.

"Another heavy dose of sanctions would be an appropriate remedy if there's no agreement at all," Senate Majority Leader Mitch McConnell told a weekly news briefing.

Rift appears between France and the United States over the wisdom of a deadline.