British Airways has formed a joint venture with China Southern. British Airways has already moved its Beijing operations to the new Daxing airport there, and flights under the joint venture are for sale beginning January 2.

Qatar Airways owns 20% of British Airways parent company IAG and announced a 5% stake in China Southern early this year.

British Airways transatlantic joint venture partner American Airlines owns a stake in China Southern – but cannot have a joint venture with them because the U.S. has no Open Skies agreement with China and would require that as a precondition for granting anti-trust immunity for such a deal. Perhaps some consolation, though, they’re expanding their Cathay Pacific codeshare to include Colombo, Seoul, Kolkata, and Bangalore.

American for its part has already written down 26% of its $200 million investment in China’s largest airline.