From the BBC today - Iran 'resumes nuclear programme'
Iran says it has resumed work at its uranium conversion facility near the city of Isfahan.
Mohammad Saeedi, deputy head of Iran's Atomic Energy Organisation, made the announcement at the Isfahan plant.
He said work at the plant where uranium conversion has taken place in the past had resumed under the supervision of the UN's nuclear watchdog.
The US and EU have warned that such a move will lead to Iran being referred to the UN Security Council.
This could lead to the imposition of Security Council sanctions.
Iran maintains its right to carry out nuclear activity for peaceful purposes, and has rejected recent European proposals for its nuclear programme, designed to give guarantees that it is not pursuing nuclear weapons.
Nuclear work at the Isfahan plant had been suspended since November 2004.
A reporter for the Reuters news agency witnessed what she says was the resumption of uranium conversion. The reporter describes two workers at the Isfahan plant lifting a barrel full of uranium yellow cake, opening its lid and feeding it into the processing line.
The reporter says that the plant had earlier been surrounded by dozens of anti-aircraft batteries.
Earlier on Monday inspectors from the UN's nuclear watchdog, the International Atomic Energy Agency, arrived at the Isfahan plant to install surveillance equipment and oversee removal of seals.
The IAEA board is due to hold an emergency meeting of the IAEA board on Tuesday. It was called by European Union states following deadlock in the talks they have been conducting with Tehran.
The Iranian government on Monday replaced its chief negotiator, Hassan Rohani, with Ali Larijani, a conservative former head of state broadcasting who is known to have close ties with Iran's supreme leader, Ali Khamenei.
The appointment was made by the conservative president, Mahmoud Ahmedinejad, two days after he was sworn in. It is being seen as a hardening of Iran's position.