A high ranking official in the Obama administration said in a press conference Friday that Iran and the West "will start drafting a comprehensive agreement for Iran's nuclear program in May."

Next week will mark the beginning of the third round of talks between Iran and the six Western powers – the United States, Russia, China, Britain, France and Germany. In recent days, nuclear experts from all seven countries have been meeting to prepare the terms for the upcoming talks.

"We arrive at the talks clear-eyed about the challenges, but wanting to make progress," said the U.S. official. "Putting this agreement together is like a Rubik's cube – finding the right combination of measures to ensure Iran cannot get a nuclear weapon."

The U.S. official stated that the pace of negotiations will "intensify" as the six-month deadline set for the talks draws closer. "We are committed to reach an agreement within six months and not within a year, and I'm certain we can make it," he said. But the real issue, he added, is "the choices Iran has to make so that the international community knows their program is peaceful."