Reuters - Iran has no plans to launch centrifuge machines able to enrich uranium at higher capacity or to alter its relations with the U.N. nuclear watchdog, the spokesman for its civilian nuclear agency was quoted as saying on Thursday.

Last week, Iran notified China, France, Germany, Russia and Britain that would scale back some commitments under its 2015 nuclear deal, a year after the United States withdrew from the pact and reimposed sanctions on Tehran.

Iran�s initial moves, involving the stockpiling of some nuclear materials, did not appear to violate the deal�s terms.

But Iran warned that unless the other signatories to the deal protect Iran�s economy from U.S. sanctions within 60 days, Tehran would start refining uranium to a fissile purity above that deemed suitable for fuelling civilian power plants.

�We do not currently have any plan to increase capacity and production process by changing the capacity of centrifuges,� Behrouz Kamalvandi, spokesman of the Atomic Energy Organization of Iran, told the semi-official news agency ISNA.

�Increasing the capacity and production process is being carried out with the same number of already installed centrifuges in Natanz (enrichment plant),� Kamalvandi said.

Regarding enhanced monitoring of Iranian nuclear sites by the IAEA under the deal, �in some stages, and to carry out some technical work, the IAEA needs to be informed in advance, which has been done and is being done,� ISNA quoted him as saying.

The restrictions on uranium enrichment accepted by Iran under the deal were aimed at extending the time it would need to produce a nuclear bomb, if it chose to, to a year from roughly 2-3 months. The United States and the IAEA believe Iran had a clandestine nuclear weapons program that it later abandoned. Tehran denies ever having had one.

The deal imposes a 15-year cap on the level of purity to which Iran can enrich uranium at 3.67 percent, far below the 90 percent of weapons grade. It is also well below the 20 percent level to which Iran enriched uranium before the deal.

Iran is also allowed to refine uranium only with its first-generation, lower-capacity IR-1 centrifuges. It can use small numbers of more advanced centrifuges for research, but without accumulating enriched uranium.

Reporting by Dubai newsroom; Editing by Mark Heinrich