The United States has launched an attack on the new Uk aviation duty, according to a report in The Sunday Times.
The criticism was made in a diplomatic note sent to the Foreign Office by the American Embassy in London last month, said the newspaper.
It said the new replacement for air-passenger duty “raises significant policy and legal issues” and asks whether the government can justify the charge when it is planning a third runway at Heathrow.
American government sources said Washington could bring a case against the UK at the International Civil Aviation Organisation or under the disputes procedure of last year’s Open Skies agreement.