Secretary of State John Kerry
Secretary of State John KerryReuters

The implementation of the Iranian nuclear deal may be only "days away", Secretary of State John Kerry declared Thursday, according to the AFP news agency.

Kerry told reporters he had spoken to Iranian Foreign Minister Mohammad Javad Zarif, who insisted Iran would live up to its promises, and added the United States would be ready to begin lifting its nuclear-related sanctions against Tehran.

"The foreign minister made it clear to me they intend to complete obligations with respect to implementation day as rapidly as possible," Kerry was quoted as having said.

"And we are currently engaged ourselves in making certain that we're prepared to move on that day and I think it could come -- without being specific -- sooner rather than later," he added.

Earlier, Kerry had hailed the deal's "Joint Comprehensive Plan of Action, from which we are days away from implementation, if all goes well."

Earlier this week, White House deputy national security adviser Ben Rhodes said the White House expected Iran to finish the work it needs to trigger implementation of the nuclear deal in the coming weeks.

That announcement came a week after  the Islamic Republic sent a major shipment of low-enriched uranium materials to Russia, which Kerry had hailed as “significant progress”.

Kerry said on Thursday Iran had shipped its stock of low-enriched uranium to Russia and that additional steps Iran was taking would leave it at least a year from achieving a nuclear capability even if it changed its mind.

"With that, Iran literally shipped out its capacity currently to build a nuclear weapon," he said, according to AFP.

"We went from two months of potential breakdown time, two to three months to nine months. And in the next days we will meet our task of being more than a year of breakout time," added Kerry.

The implementation of the deal comes despite a December 2 report from the International Atomic Energy Agency (IAEA) which concluded that Iran made a "coordinated" effort to develop nuclear weapons in the past, although the efforts apparently ended at an early stage.

According to the report, most of the dedicated work took place before 2003, though some parts continued until 2009.