By Bethany Bell
BBC News, Vienna
**The UN nuclear watchdog says Iran has slowed its enriched uranium production, but continues to install the centrifuge machines needed for the process.**The findings are in the latest report of the International Atomic Energy Agency (IAEA).
It said Iran was not co-operating with the agency to clear up questions about a possible military dimension to its nuclear programme.
It said it was critical that Tehran clarify the outstanding questions.
In a confidential report obtained by the BBC, the IAEA said Iran was continuing its sensitive uranium enrichment work, in defiance of the UN Security Council. But it said there has been a slowdown in production.
A senior UN official said the reasons for the slowdown were not clear.
Enriched uranium can be used for civilian nuclear power or to make atomic bombs.
The report said Iran had agreed to improved monitoring at the enrichment plant at Natanz.
The report said the agency had not had meaningful talks with Iran on its controversial nuclear programme for over a year.
The United States and a number of its allies believe Iran is secretly trying to develop nuclear weapons - a charge Tehran denies.