The International Atomic Energy Agency is to hold second day of talks in Vienna Wednesday on how to respond to Iran's resumption of low-level uranium conversion.

Iran this week restarted parts of the conversion process at its Isfahan nuclear plant.

Iranian officials say they expect to get access to sealed sensitive parts of the plant Wednesday, after an IAEA surveillance system begins functioning. The step will allow the facility to operate at full capacity.

The European Union, with U.S. backing, has threatened to refer Iran to the U.N. Security Council, which could impose sanctions if it finds Tehran has violated the Nuclear Non-Proliferation treaty.

Iran's new President Mahmoud Ahmadinejad said Tuesday that European incentives aimed at persuading Iran to end its nuclear fuel program are an insult to the Iranian nation.

Some information for this report provided by AFP and Reuters.