Russian Deputy Foreign Minister Sergei Ryabkov has accused the United States of exerting pressure on Turkey's national airline to bar Russian citizens from flights bound to Mexico. His comments came after Moscow's embassy in Ankara this week complained that some Russian airline passengers were being indiscriminately denied boarding while transiting on Turkish Airlines flights from Istanbul to some Latin American countries. "Specifically in relation to Mexico, the reason, I think, is easy to guess", Ryabkov was quoted late on Wednesday as saying by the TASS state news agency.