Transcript for This day in history: Sept. 27, 2013

Today President Obama surprised everyone announcing he had a personal phone conversation. With the new president of Iran the first direct contact between leaders since 1979. So the question tonight is this the best chance for a breakthrough in the Middle East in thirty years and will the new leader of Iran really deliver. ABC's chief White House correspondent Jonathan Karl on these latest developments from the White House job. History was made today Diane with that fifteen minute phone call it potential opening. To a country the US is accused of trying to build nuclear weapons and supporting terrorism. Before this the storming of the US embassy in Tehran and 400 in 44 day hostage crisis that followed. Has a US president spoken to at a Ronnie and president. The very fact that this was the first communications between an American and wrong of president. Since 1979. Underscores the deep mistrust between our countries. But it also indicates the prospect of moving beyond that difficult history. News of the call first broke with a tweet from Iran's president shortly before President Obama announced it. Holly had turned down a face to face meeting when both men were in New York on Tuesday but the call was his idea. For Holly's band in New York all week speak yet the UN and vowing warmer relations with the United States. The obstacles are huge for years war with the wrong. I seems more likely to diplomatic progress but the president says he sees a chance for a big change beginning with a renewed talks on Iran's nuclear program. I believe we've got a responsibility. To pursue diplomacy. We have a unique opportunity to make progress. With the new leadership in Tehran right after the president touted his historic conversation with the president of Iran he lashed out at a group he hasn't been talking to. Republicans in congress. Who we blame for putting the government on a path to shut down in just three days nobody gets to threaten the full faith and credit of the United States. Just to extract political concessions. Norm gets hurt our economy. And millions of innocent people just because there a couple of laws that. You do not like. While history was made with the Obama rock on the phone conversation there have been no phone calls this week between the president. And the speaker of the house Diane it is no exaggeration to say that the president has made more progress this week with the wrong that he has with the Republicans in congress.

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