Iran's latest defiance over its uranium enrichment was "another signal" that it is defying the international community to give up such activities, State Department spokesman Sean McCormack said Monday.

"This is another signal that Iran is defying the international community," McCormack said.

"There is a way out. There is a negotiation alternative should the Iranian leadership choose to take it. To date they have not and today is another indication that they have chosen not to," McCormack said.

U.S. Secretary of State Condoleezza Rice has said that she is willing to meet Iranian officials on condition that Teheran suspends uranium enrichment activities.

Earlier Monday, Iranian President Mahmoud Ahmadinejad announced that Iran has begun enriching uranium with 3,000 centrifuges and is capable of enriching nuclear fuel "on an industrial scale."

The United States has accused Iran of trying to develop nuclear weapons under the cover of a civilian nuclear program. Iran has denied the charges.

Source: Xinhua