Iran said on Monday that a Venezuelan airplane grounded in Argentina is part of a “propaganda” campaign against Tehran, amid tensions with Western countries over negotiations to revive a 2015 nuclear deal. The Venezuelan Boeing 747 cargo plane, reportedly carrying car parts and with 14 Venezuelan and five Iranian crew members, has been held in Argentina’s Ezeiza airport after the authorities questioned its reasons for landing last week. The grounding came days before Venezuelan President Nicolas Maduro visited Tehran on Saturday, where Iran and Venezuela signed a 20-year deal on cooperation be…