VIENNA (AP) -- Talks over Iran's nuclear program are making little headway, with Tehran resisting U.S.-led efforts to crimp activities that could be turned toward making weapons, diplomats said Monday.
As negotiations move closer to a July 20 target date for a deal, both sides are trying to plug holes in a sketchy draft agreement.
Five days into the latest round of talks between Iran and six global powers, two diplomats told The Associated Press that there is still a disagreement on the constraints Iran is ready to accept in exchange for a full end to the sanctions stifling its economy. The diplomats demanded anonymity because they are not authorized to discuss the confidential negotiations.
Tehran's resistance was underscored late Monday when Iran's supreme leader Ayatollah Ali Khamenei rejected pressure by the U.S. and its allies at the Vienna talks to force Iran into making concessions He said the Islamic republic would not give in to attempts by the West to greatly restrict its uranium enrichment program.
Khamenei told top officials that the country should plan as if sanctions will remain in place so that Iran will be immune to outside threats.
Khamenei said in a state television broadcast that the U.S. goal at the nuclear talks is to convince Iran to limit its uranium enrichment capacity to 10,000 Separative Work Units (SWUs) while Tehran needs at least 190,000 SWUs.
The biggest hurdle remains uranium enrichment, a process that can make reactor fuel or the core of a nuclear weapon depending on the grade of material produced. Iran, which insists it does not want such arms, now has nearly 20,000 centrifuges either on standby or churning out reactor-grade fuel.
Tehran has long demanded that it be allowed to run up to 50,000 centrifuges to power its one existing nuclear reactor, and the two diplomats said Monday's expert talks began with no formal change in that position.
The United States wants no more than a small fraction of that number. Its strongest backers at the negotiating table are Britain, France and Germany, with Russia and China leaning to agreeing on any deal acceptable to Tehran and Washington.
Khamenei said Iran is prepared to give guarantees that it won't weaponize its nuclear program but said the U.S., which has a record of using nuclear weapons during World War II, has no right to be worried about it.
The diplomats said there's still disagreement over how to minimize proliferation dangers from a nearly built reactor that would produce substantial amounts of plutonium -- like enriched uranium, a potential pathway to nuclear arms.
In addition, Iran is resisting pressure to turn a uranium enrichment site dug into a mountain as protection against air attack to another use, they said. Differences also exist over the length of any agreement placing limits on Tehran's nuclear activities.
Khamenei rejected demands from the West that Iran shut down the underground Fordo enrichment site.
"On the Fordo facility, they say it should be shut down because it is not accessible and cannot be damaged. This is laughable," Kahmenei said. "We are sure our negotiating team won't agree that the rights of the country and the nation's dignity be encroached," he said.
Khamenei said "military threats" and "sanctions" are two instruments used by the U.S. to pressure Iran, but insisted that such tactics would not force Iran to give in.
"Sanctions must be thwarted through struggles in the field of resistance economy. And military threats are just words since it's not affordable," he said. "Economic planning should take this assumption that the enemy won't reduce sanctions one iota. Don't let the enemy affect your calculations."
Khamenei, however, offered words of strong support for moderate President Hassan Rouhani, whose administration has been accused by hardliners of selling out Iran's nuclear achievements.
"I endorse and support the government and will use everything in my power to back it ... we trust our negotiating team," he said.
Iran and the six-nation group signed an interim deal last November in Geneva that curtailed Iran's enrichment program in return for an easing of some sanctions. Under the historic deal, Tehran stopped enrichment of uranium to 20 percent - which is just steps away from bomb-making grade - in exchange for the easing of some Western sanctions. It has diluted half of its 20 percent enriched uranium into 5 percent and is to turn the remaining half into oxide, which is very difficult to be used for bomb-making materials.
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