President Barack Obama said Sunday that if world powers and Iran cannot agree to a verifiable deal, the U.S. will walk away from talks.

"If we cannot verify that they are not going to obtain a nuclear weapon, that there's a breakout period so that even if they cheated we would be able to have enough time to take action - if we don't have that kind of deal, then we're not going to take it," Obama said during an exclusive interview with American broadcaster CBS.

The U.S. and its partners in the P5+1, which includes France, the U.S., the U.K., Russia and China plus Germany, have until the end of the month to agree to a political framework agreement with Iran on its nuclear program.

"Over the next month or so, we're going to be able to determine whether or not their system is able to accept what would be an extraordinarily reasonable deal, if in fact, as they say, they are only interested in peaceful nuclear programs," Obama said.

"If there is no deal then we walk away," he added.

A final deadline for a comprehensive accord is set for the end of June.

Negotiators have reportedly been attempting to limit Iran's nuclear enrichment program to create a situation in which it would take the country roughly a year for it to develop enough fuel to build a nuclear weapon if it violated an agreement.

Obama stressed on Sunday that "we're not losing anything through these talks," which have been governed by an interim agreement since January 2014 that places restrictions on Iran's enrichment activities in exchange for limited sanctions relief.

But others have disagreed, most prominently Israeli Prime Minister Benjamin Netanyahu, who addressed a joint session of Congress last week to rally opposition to any prospective deal.

He said that a deal "doesn't block Iran's path to a bomb, it paves Iran's path to a bomb."