The White House says Iran is lashing out at the world to "distract attention" from the damage that international sanctions are having at home.
Iran is claiming Wednesday that it has achieved two major advances in its program to master production of nuclear fuel, a defiant move in response to increasingly tough Western sanctions over its disputed nuclear program.
Iran state media also reports steps to cut oil exports to six European countries in retaliation for new European Union sanctions, including a ban on Iranian oil.
White House press secretary Jay Carney says such "defiant acts" show that Iran's leaders are under pressure.
State Department spokeswoman Victoria Nuland said said on Wednesday that, "Iran is clearly feeling the pressure of its international and diplomatic isolation, of the increasing economic pressure on it, unprecedented sanctions which are growing, that the international community is continuing to strengthen."
The sanctions are intended to persuade Iran to back down. Iran has refused, although it signaled Wednesday that it is willing to return to talks.
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