"We had only sought a resolution that would affirm the unity of the six (five permanent U.N. Security Council members plus Germany), and to let the Iranians know that that unity is very strong and that we'll be moving forward," U.S. Secretary of State Condoleezza Rice said during a media availability with the Kazakhstan foreign minister in Washington.

Last weekend, the U.N. Security Council unanimously passed a resolution reaffirming existing sanctions against Iran for not being opened enough about its nuclear program, which the United States and other Western nations say is being used to develop nuclear weapons.

Iran called the vote "unwarranted" and "unjustifiable," saying it would pursue its uranium enrichment program that Tehran said was for peaceful purposes.