Talks on restoring a deal to curb Iran’s nuclear programme and ease sanctions are near conclusion, a Russian envoy said on Tuesday, and sources close to the negotiations said a prisoner swap between Iran and the United States is expected soon. “Apparently the negotiations on restoration of #JCPOA are about to cross the finish line,” Mikhail Ulyanov said on Twitter, using the 2015 agreement’s full name, the Joint Comprehensive Plan of Action. Reuters reported last week that a US-Iranian deal was taking shape in Vienna after months of talks between Tehran and major powers to revive the nuclear d…