AIRLINES

Britain Threatens to Curtail U.S. Airline Flights: The government said it has warned U.S. officials that it will ban some U.S. airline flights into Heathrow Airport if the United States continues to restrict British Airways’ ability to market its services in America. If it does take action, Britain will ban one flight a week each by American Airlines from Chicago to London and one weekly flight by United Airlines from Washington to London, beginning Jan. 12. The United States and Britain have been negotiating in an attempt to reform the treaty that governs air travel between the two countries.