Iran’s nuclear chief says Tehran will soon tell the U.N. nuclear agency when it can inspect a newly disclosed uranium enrichment plant.

Ali Akbar Salehi made the announcement in an interview released by state-run television Tuesday, just two days before Tehran is to discuss its nuclear program with world powers in Geneva.

Iranian lawmakers are warning the U.S. and other world powers against repeating past mistakes during Thursday’s talks.

They issued a statement Tuesday saying the talks are a “historic opportunity” to move past the deadlock on the nuclear issue.

The United States is threatening Iran with tougher sanctions if it does not fully reveal its nuclear activities and allow U.N. inspectors to visit the new plant Tehran acknowledged last week it is developing.

China urged calm Tuesday after Tehran drew international condemnation by testing its longest-range missiles on Monday.

The Foreign Ministry in Beijing called on all sides to resolve the problem through negotiations.

Western nations suspect Iran is building a nuclear weapon, but Tehran says it is simply pursuing nuclear energy.

Iran’s nuclear chief says Tehran has informed the U.N. International Atomic Energy Agency that the new plant will produce enriched uranium at a level (five percent) consistent with its nuclear energy program.

Some information for this report was provided by AFP, AP and Reuters.