US Secretary of State John Kerry designated as “provocative” Iran’s opening of two uranium and milling plants on Tuesday to speed up its nuclear drive.Kerry was speaking to reporters at Ben-Gurion Airport as he was boarding a plane to London to participate in the G8 meeting, during the final moments of a three-day visit to Israel and the Palestinian territories.He compared the opening of the Saghand 1 and 2 uranium mines in Iran’s central city of Yazd and the Shahid Rezaeinejad yellow cake factory to North Korea’s threatening nuclear actions.It is not “unlike the DPRK, where Kim Jong-un has decided to reopen his enrichment procedures by rebuilding a facility that had been part of an agreement to destroy,” Kerry said.“In the same way as that is provocative, to open up yellow cake production and to make any step that increases the rapidity with which you move towards enriched fissile material raises the potential of questions, if not even threat. And I think that is not constructive,” he added.During his visit, the secretary of state discussed Iran’s nuclear drive and the dangers of Syria’s continued civil war with Prime Minister Binyamin Netanyahu and President Shimon Peres.Reuters contributed to this story.Before meeting with Netanyahu in Jerusalem, he told reporters that the US won’t allow Iran to indefinitely drag out negotiations over its nuclear program.“Iran cannot have and will not have a nuclear weapon,” Kerry stated flatly.“We are open to negotiation, but it is not an openended, endless negotiation; it cannot be used as an excuse for other efforts to try to break out with respect to a nuclear weapon.”The US has made it clear to Israel and to the international community that it is serious in this regard.“President [Barack] Obama doesn’t bluff; he’s made that very clear to me. And we hope the Iranians will come back to the table with a very serious proposal,” Kerry said.He spoke as Western diplomats scramble to keep alive negotiations with Tehran over the possibility that it would voluntarily halt its nuclear program.At a meeting in the Kazakh city of Almaty on Friday and Saturday, the six nations – the United States, Russia, China, France, Britain and Germany – tried to persuade Iran to give up its most sensitive uranium-enrichment work to allay concerns that Tehran is seeking the means to make atom bombs. Iranian negotiators did not accept the offer – coupled with a pledge of modest relief from crippling economic sanctions – and the two sides failed to even agree to meet again.World powers believe there are enough grounds to keep talking to Iran about its disputed nuclear program, a senior Western diplomat said on Monday, even though the latest round of negotiations made little apparent progress.“There is enough substance for these negotiations to continue,” the diplomat, speaking on condition of anonymity, told reporters. “I would not expect a breakdown.”EU foreign policy chief Catherine Ashton, who oversees diplomatic contacts with Iran on behalf of the six nations, will discuss plans for further engagement with Iran’s chief negotiator Saeed Jalili in the coming days.Kerry told reporters at Ben- Gurion International airport that he thinks “it’s fair to say that we were hoping that there would be a more fulsome presentation in Almaty that would have laid out with greater specificity and greater breadth what could have been done to try to reduce the tensions over Iran’s nuclear program.”In Jerusalem on Monday morning, Netanyahu told Kerry that Iran “cannot be allowed to continue its nuclear weapons program.We must not allow it do to so in defiance of the entire international community.”“I think everyone understands that Iran has been running out the clock, has been using the talks to continue to advance its nuclear program,” the prime minister said. “I think we also understand what it means for the world to have rogue states with nuclear weapons.”Turning to the Syrian civil war, Netanyahu said, “The fragmentation of that country is creating a situation where one of the most dangerous stockpiles of weapons in the word is now becoming accessible to terrorists of every shade and hue.”At Ben-Gurion Airport, Kerry said he would meet Syrian opposition members while in London, adding that it is Obama’s preference to find a diplomatic solution for the battle between rebels and the supporters of Syrian President Bashar Assad.His hope, he said, would be stop the killing of civilians in that conflict by the “legitimate transfer of governing responsibility to an independent entity.”The secretary of state said that both in London and after his return to Washington, he would seek ways to convince Assad to accept that solution.Kerry’s trip will be followed by the arrivial of Defense Secretary Chuck Hagel for his visit on April 21-23. This is his first trip to Israel since taking office.Separately, International Relations Minister Yuval Steinitz spoke about the dangers of a nuclear Iran with Canadian Foreign Minister John Baird.He thanked Baird for Canada’s strong position on the need to take all necessary measures to block Iranian uranium production.Baird also met with Peres and Netanyahu and spoke with them as well about Iran and Syria.