British Airways and American Airlines today asked for US approval to place their codes on most of one another's flights, with the key exception of journeys between the US and London.
The bid follows a failed attempt earlier this year by Europe's biggest airline British Airways and leading US carrier American Airlines to deepen their transatlantic ties.
The firms decided the price demanded by regulators - the surrender of hundreds of weekly take-off and landing slots - was too high.
American, owned by AMR Corp, and BA said in a joint statement today they had filed an application with the US Department of Transportation for code-sharing permitted underthe current provisions of the US-UK Air Services Agreement.
The two airlines are leading lights in the eight-member Oneworld global airline grouping, which also includes Cathay Pacific Airways Ltd and Qantas Airways.