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By Louis Charbonneau and Justyna Pawlak
UNITED NATIONS/BRUSSELS, Jan 27 (Reuters) - - The first round of talks between Iran and six world powers on a long-term deal for Tehran to curb parts of its nuclear program in exchange for a gradually end to sanctions is expected to take place next month in New York, Western officials said on Monday.
"Waiting for official announcement, which should be soon," a Western official told Reuters about tentative plans to hold the talks as early as mid-February at U.N. headquarters in New York City. "One of the reasons it's moving to new York is the UN infrastructure, similar to Geneva."
Several Western diplomats, also speaking on condition of anonymity, confirmed the official's remarks. One senior Western diplomat told Reuters that the six powers were looking at the early part of the week of Feb. 16, though the talks were unlikely to begin before Feb. 18 due to a U.S. holiday.
Last week the United States and the European Union began following through on promised sanctions relief for Iran covering oil exports, trade in precious metals and automotive services as part of a nuclear agreement signed in November that began taking effect on Jan. 20, U.S. officials said.
In exchange for steps that Tehran had taken to halt its most sensitive nuclear-related activity, the White House said the United States, Britain, France, Germany, Russia, China and the European Union will "follow through on our commitment to begin to provide the modest relief agreed to with Iran."
A U.S. official said Iran was currently exporting about 60 percent less oil than it was two years ago and would be held to those reduced levels.
Iran is under U.S., EU and U.N. Security Council sanctions for refusing to halt uranium enrichment and other sensitive atomic work that could help it develop weapons.
Tehran rejects allegations from Western nations and their allies that it is seeking the capability to produce nuclear arms, insisting its atomic ambitions are limited to the peaceful generation of electricity.
The Nov. 24 interim deal between Iran and the five permanent U.N. Security Council members plus Germany took nearly two months to hammer out in three rounds of talks in Geneva late last year. Western diplomats say that negotiations on a long-term deal will likely take much longer.
Iranian President Hassan Rouhani said last week at the World Economic Forum in Davos, Switzerland that Iran is determined to negotiate a comprehensive deal on its nuclear program with the six world powers so it can develop its battered economy, inviting Western companies to seize opportunities now.
The Nov. 24 interim deal is valid for six months, though it can be renewed based on mutual agreement. (Reporting by Louis Charbonneau and Justyna Pawlak; Editing by James Dalgleish and David Gregorio)