European Union governments agreed to deregulate the $18 billion trans-Atlantic airline market, endorsing a treaty with the U.S. that will spur competition, encourage mergers and end decades of national protection for carriers including British Airways. Tourism ministers approved an "open-skies" accord allowing EU airlines to make U.S. flights from any of the bloc's nations instead of just from their home country. The deal will also scrap rules letting only British Airways, Virgin Atlantic Airways, American Airlines and United Airlines fly between the U.S. and London's Heathrow airport. The accord will lower airline fares and increase annual EU-U.S. traffic by 26 million passengers to about 73 million over five years.