American Airlines is to add a second daily flight between Heathrow and Los Angeles from March 2015.
The carrier, which operates a transatlantic joint business with British Airways, will use a three-class Boeing 777-300ER on the new flight starting on March 29.
The additional service will mean that American and BA will operate a total of four daily flights on the Heathrow-LAX route.
Andrew Nocella, American’s chief marketing officer, said: “As the premier airline in Los Angeles, this additional frequency from London caters to our high-end customers in both cities.
“These customers demand a world-class travel experience including true first and business class cabins on modern aircraft serving the best network at LAX.”