In an exclusive wide-ranging interview with Newsweek’s Lally Weymouth and editors from the Washington Post, Iranian President Mahmoud Ahmadinejad discussed his upcoming talks with the United States, his opinion of President Obama, his continued denial of the Holocaust as well as the U.S.-led effort in Afghanistan, which he views as doomed. In it he previewed his offer to purchase enriched uranium from the United States for medicinal purposes, which proliferation experts say is likely a non-starter. Excerpts: