Closing in on nuclear deal, U.S. demands 'tough choices' from Iran

(Reuters) - The United States and Iran inched closer to a political deal that would set the stage for a landmark nuclear agreement, but a U.S. official warned on Monday that Iran must make tough choices to allay fears about its atomic ambitions.

U.S. Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif held nearly five hours of talks in the Swiss city of Lausanne before the Iranian delegation headed to Brussels for meetings with European ministers.

After the Lausanne talks, a senior U.S. official said it was not clear if an end-March deadline for a framework agreement between Iran and six major powers could be met.

"We are trying to get there but quite frankly we still do not know if we will be able to," the official told reporters on condition of anonymity. "Iran still has to make some very tough and necessary choices to address the significant concerns that remain about its nuclear program."

The official did not elaborate but added that the Iranian delegation also raised in the meeting with Kerry an "ill-timed and ill-advised" letter from 47 Republican senators to Iran's leadership warning that they could undo any deal President Barack Obama made with them.

"These kinds of distractions are not helpful when we're talking about something so serious," the official added.

The U.S. official said the sides would work through the end of the month if needed to secure a deal. Talks are expected to resume on Tuesday.

Speaking to reporters in Brussels, French Foreign Minister Laurent Fabius said progress had made in the talks but "important points" were unresolved.

With the Iranian new year holiday of Norouz approaching this weekend, officials close to the talks say it will be difficult to complete a political agreement this week. If it is not possible by the weekend, the talks could reconvene in the final days of March.

Zarif said all sides needed to keep talking this week to see what could be achieved.

"On some issues we are closer to a solution and based on this we can say solutions are within reach. At the same time, we are apart on some issues," he told the Iranian news agency IRNA. Read More 

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