TEHRAN, Iran â€"  Iran's nuclear chief says there are no reasons at the moment to halt production of uranium enriched to 20 percent, a key demand of world powers.

Fereidoun Abbasi was quoted by state TV Sunday as saying Iran will continue the higher enrichment for a medical research reactor that produces isotopes for cancer treatment.

Abbasi's statement echoes Iran's objections last week in Baghdad to suspending 20 percent enrichment in exchange for a U.S.-supported package that would include supplying Iran with isotopes. Iran seeks to have Western sanctions eased before considering any deals.

The U.S. and allies worry that the 20 percent enriched material could be turned quickly into weapons grade uranium. Iran denies it seeks nuclear arms.

Abbasi also said Iran plans to build at least two new nuclear power plants next to an existing facility that became operational with Russia's help last year.

Iran is in the very early stages of planning the new 1,000-megawatt nuclear power plants, it may begin construction within a year or two, he said.

Iran has repeatedly said in recent years that it is planning to build more nuclear power plants but nothing has been offered to show that any work is under way.

Iran's first power plant went into operation last May at the southern coastal city of Bushehr.

The West suspect Iran is pursuing a nuclear weapon program, a charge Iran denies.