Nightly News | January 08, 2012
>>> overseas tonight, the war of words between the u.s. and iran is escalating over the nuclear program and beyond. today, the iranians made new threats. we get the latest tonight from our tehran bureau chief.
>> reporter: iran announced today it has begun to enrich uranium at a second underground facility well protected from possible air strikes . iran insists its nuclear program is for peaceful purposes, but the west suspects iran of developing a nuclear weapons program . still, defense secretary leon panetta had a blunt warning today about nuclear weapons .
>> they need to know that if they take that step, that they're going to get stopped.
>> reporter: president obama approved but not yet implemented new sanctions that would target its ability to sell oil abroad. today a senior iranian official said iran wouldn't allow a drop of oil to pass through the strait of hormuz if petroleum exports are blocked. a fifth of oil passes through the water way.
>> the united states will not tolerate blocking of the straits of hormuz, that's another red line for us and we will respond to that.
>> reporter: iran also warned the carrier " uss stennis " not to return to the persian gulf . that same carrier helped rescue 11 iranian fishermen from pirates last week. while the government called it a positive and humanitarian act, iranian state news agencies dismissed it as a hollywood movie . lester?