Nations to Mull New Sanctions Against Iran for Nuclear Program

The countries considering the sanctions are the five permanent members of the U.N. Security Council -- the United States, France, Britain, China and Russia -- and Germany.

The U.S. State Department said discussions were in their "beginning phase" and no timeframe for a decision had been set, Reuters reported. Three previous rounds of U.N. sanctions took months to approve. China and Russia have shown reluctance to sanctions in the past.

"We are very disappointed that Iran has yet again failed to give Javier Solana a clear answer to the ... generous incentives package," State Department spokesman Gonzalo Gallegos told reporters, according to the Associated Press. "We agreed that we have no choice but to pursue further measures against Iran."

Iran has refused to stop enriching uranium, which can be used to build an atom bomb, despite economic and other incentives offered by the six countries.

Iran gave a one-page letter to Solana on Tuesday that was supposed to either accept or reject an offer by the six powers to refrain from more U.N. penalties if Iran freezes expansion of its nuclear work. Instead, Iran reiterated its right to pursue peaceful nuclear activities and said it would not give a definitive offer to the incentives package until it got some questions answered, the AP reported.

"The letter that we received yesterday appears to be a stalling tactic," Gallegos said.

France also said the response was insufficient.

France regrets that Iran "has again chosen not to provide a clear response," said Foreign Ministry spokesman Romain Nadal in Paris, according to the AP.

Russia's U.N. ambassador said that Moscow had not set a deadline for Iran to respond to the "freeze for freeze" offer, and that dialogue continued, Reuters reported.

Ambassador Vitaly Churkin said the six powers would hold talks about Iran's disputed nuclear program at a ministerial level in September.

An official from the United Nations' International Atomic Energy Agency planned to travel to Iran on Thursday.