Negotiators in Vienna have failed to meet a Monday deadline for curbing Iran’s nuclear program. U.S. Secretary of State John Kerry said “real and substantial” progress had been made during the talks that have been extended until next June. CCTV America’s Jack Barton reported from Vienna.

It was all smiles in Vienna for the five permanent members of the United Nation’s Security Council, plus Germany and the EU’s envoy Catherine Ashton. But their combined efforts failed to result in a comprehensive agreement with Iran over its nuclear program, other than an extension of the deadline.

“We are jointly, the P5+1 [the five permanent members of the security council and Germany], six nations and Iran, extending these talks for seven months with the very specific goal of finishing the political agreement within four months, and with the understanding that we will go to work immediately, meet again very shortly and if we can do it sooner, we will do it sooner,” Kerry SAID.

Negotiators insisted there had been progress and that the talks have momentum.

“We need to use this momentum that really held up in Vienna and not rest but continue to negotiate as consistently and intensively in the next few days and weeks,” said Frank Walter Steinmeier, Germany’s foreign minister.

Despite the talk of progress, diplomats said large gaps remained on the issue of how many uranium enriching centrifuges Iran would be prepared to dismantle.

Some officials privately criticized the extension, which appears to favor Iran as its nuclear program will remain frozen but intact, without any of the reductions demanded by the United States.

Perhaps anticipating criticism from congressional conservatives at home, Kerry pointed out that Iran had abided by the interim agreement and was not on the verge of possessing an atomic bomb.

“A year ago, [Iran had] around 200 kilograms [441 pounds] of 20-percent enriched uranium in [a] form that could be quickly enriched into a weapons grade level. Today, Iran has no such 20-percent enriched uranium, zero, none,” Kerry said.

Talks are expected to resume next month although a venue has not yet been set.

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