The agreement, announced by U.S. Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov, will be put into place beginning at sundown on Monday.
Britain's top political parties are scrambling to find new leaders as lame duck Prime Minister David Cameron heads to Brussels to attend European Commission meetings and reassure continental allies.
Kerry is the highest-ranking U.S. official ever to visit the site. He honored the 140,000 Japanese who died in the U.S. attack on the city, but did not apologize for the bombing there and in Nagasaki.
Secretary of State John Kerry tells NPR that Iran would use the deal's failure as an excuse to enrich uranium. He also says efforts to thwart warming diplomatic relations with Cuba would hurt the U.S.
In an interview, Kerry says that he was prepared to — and did — walk away from nuclear negotiations with Iran, but that Congress rejecting the eventual agreement would cost the U.S. all credibility.
NPR gets the back story of the years-long negotiations that produced the Iran nuclear deal from journalist Robin Wright. She's traveled to Tehran and spoken with negotiators on both sides of the deal.
Officials in Vienna tell NPR's Peter Kenyon that preparations are being made today to announce a historic accord that will restrict Iran's nuclear program and lift some economic sanctions.
Saudi Arabia says the cease-fire will help get much-needed humanitarian aid into Yemen, but the offer is good only if Houthi rebels comply with the deal.