LONDON (Reuters) – The National Iranian Oil Company (NIOC) and Russian gas producer Gazprom signed on Tuesday a memorandum of understanding worth around $40 billion, Iran’s oil ministry’s news agency SHANA reported. The deal was signed during an online ceremony by the CEOs of both companies on the day Russian President Vladimir Putin arrived in Tehran for a summit with his Iranian and Turkish counterparts. (Reporting by Bozorgmehr Sharafedin, Editing by Louise Heavens)