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VIENNA, Nov 24 (Reuters) - Iran expects a deal it reached with world powers in July, under which sanctions will be lifted in return for it scaling down its nuclear programme, to be implemented at the start of next year, Iranian nuclear negotiator Abbas Araqchi said on Tuesday.

"We expect early January," Araqchi told reporters after meeting the director general of the International Atomic Energy Agency (IAEA), which is tasked with verifying whether Iran is keeping its commitments under the deal.

Iran is holding parliamentary elections on Feb. 26 and diplomats say Tehran has been working hard to fulfil its commitments under the nuclear deal before that date.

Iran's President Hassan Rouhani won by a landslide in 2013, promising a rapprochement with the West and an economic revival based on sanctions' relief.

The IAEA said in a confidential report last week that Iran had disconnected almost a quarter of its uranium-enriching centrifuges in less than a month.

Tehran is also required to reduce its stockpile of low-enriched uranium -- currently around 8,300 kg -- to 300 kg before the deal can be implemented.

Iran has reached a deal with Russia to export some of its enriched uranium to Russia in exchange for yellowcake, a form of uranium which has been mined but not yet enriched, Araqchi said.

Araqchi said that swap arrangement would be implemented only after the IAEA has closed its investigation into the so-called possible military dimensions (PMD) of Iran's nuclear past.

The IAEA's Board of Governors is due to discuss the agency's assessment of the PMD file on Dec. 15.

(Reporting By Shadia Nasralla; editing by Francois Murphy and Richard Balmforth) ((Shadia.Nasralla@thomsonreuters.com; +43 153 11 2256; +43 664 390 6505;))

Keywords: IRAN NUCLEAR/