Iran's ability to enrich uranium troubles U.S. lawmakers

(Reuters) - U.S. lawmakers in the House of Representatives said on Wednesday they are concerned about Iran's ability to continue enriching uranium under the interim agreement on Tehran's disputed nuclear program, an issue they are likely to press as global powers attempt to reach a final agreement.

The concerns showed that House lawmakers could be willing to push for a new sanctions package next year that would define what Congress would be willing to accept in a final deal with Iran.

The six-month interim deal made by the United States, five other world powers and Iran in Geneva last month gives International Atomic Energy Agency inspectors greater access to Iran's nuclear facilities and requires the Islamic Republic to halt its enrichment of higher grade uranium.

But it allows Iran to continue enriching uranium up to 5 percent purity for generating nuclear power. That level is well below 20 percent pure uranium which can be converted relatively easily into weapons-grade material. But many lawmakers worry any enrichment in Iran is too much.

"It would have been better if Iran during the course of the negotiations would stop enriching. I don't think that would have been too much to ask Iran," said Representative Eliot Engel, a Democrat and ranking member of the House Foreign Affairs Committee.

"It makes me question the sincerity of the Iranians," Engel told reporters after a classified House briefing with Wendy Sherman, the State Department's lead negotiator on Iran's nuclear program.

Representative Michele Bachmann, a Minnesota Republican, said after the briefing that she suspects Iran would be able to continue to enrich even after a final deal.

"Unfortunately I believe the Obama administration, from what we have heard today, may very well allow Iran to maintain the right to enrich," she said. "The only way we will ensure that Iran does not ultimately obtain a nuclear weapon will be if they dismantle the centrifuges and also relinquish the enriched uranium that they have now."

Representative Tom Price, a Republican from Georgia, said on Tuesday that the Obama administration had given Iran too much in the interim agreement. "I think we have to be much more aggressive in pushing back on the administration on what they've done so far," he said before lawmakers met with Sherman.

The interim agreement between Iran, the United States, France, Russia, China, Britain and Germany leaves open the question of whether Iran can continue to enrich uranium to low levels and explains that a comprehensive deal would involve a "mutually defined" enrichment program with "practical limits and transparency measures" to ensure that it was for peaceful purposes.

Dutch Ruppersberger, the top Democrat on the House Intelligence Committee, signaled he was not bothered by the fact that Iran can continue to enrich low level uranium as world powers work toward a comprehensive deal. "You're talking (about) a situation where most of the sanctions are still in place," he said adding that the agreement allows nuclear inspectors better access than they had before.

Lawmakers in the Republican-led House are waiting for the Senate to move on a bill the House passed this summer 400-20 that would place new sanctions on Iran and drive down the lifeblood of its economy, oil exports, to almost nothing.

Some sanctions backers in the Senate are seeking to pass new sanctions that would not take effect unless Iran violated the interim agreement.

The White House said this week it opposes a fresh effort by some members of the Senate to impose new sanctions on Iran, even if they did not take effect for months, because it could prod Tehran and the other world powers to say Washington had negotiated in bad faith.

(Additional reporting by Caren Bohan)