Iran’s chief negotiator said Sunday that Tehran would not agree to any deal with the United States unless it fully secures Iranian rights, as reports emerged that Washington had sent a tougher peace proposal back to Iran. Any tweaks to the proposal could further delay an agreement to formally end the Middle East war and reopen the Strait of Hormuz after weeks of fraught negotiations marked by sharp rhetoric and occasional flare-ups of violence. JOIN US ON TELEGRAM Follow our coverage of the war