MOSCOW, March 31 (Reuters) - Russia’s Ministry of Transport said on Saturday that Moscow would demand an official explanation from Britain for why a Russian Aeroflot passenger plane had been subjected to a search at Heathrow airport on Friday.

The Russian embassy in Britain complained about the search at the time.

On Saturday, the Ministry of Transport said it wanted to know what had happened. “If there is no explanation, the Russian side will deem the actions towards our plane as illegal and also reserve the right to take similar action against British airlines,” it said in a statement. (Reporting by Andrew Osborn Editing by Catherine Evans)