LONDON, Dec 20 (Reuters) - Prime Minister Boris Johnson will chair an emergency response meeting on Monday to discuss international travel, in particular the flow of freight in and out of Britain, a spokeswoman for his office said on Sunday. “The prime minister will chair a COBR (emergency response) meeting tomorrow to discuss the situation regarding international travel, in particular the steady flow of freight into and out of the UK. Further meetings are happening this evening and tomorrow morning to ensure robust plans are in place,” the spokeswoman said. (Reporting by Elizabeth Piper; Editing by Daniel Wallis)