Swiss banks' access to Europe is under threat following Britain's vote to leave the European Union. The Swiss Bankers Association wants to throw more weight into lobbying efforts.

Not just London should be part of the alliance, but Hong Kong and Singapore too. Lobby chairman Patrick Odier, who is stepping down this year and will be replaced by Herbert Scheidt, is floating the idea of a «F4,» a spokeswoman for the association said, confirming a «Financial Times» report.

Britain's Single Market Access Under Threat

«The financial centers have more weight when they approach regulation and politics with one voice,» the spokeswoman said. The lobby is in contact with Hong Kong and Singapore as well we with London.

Should the U.K. exit the EU, British banks will have considerable trouble distributing their products and services in the single market.

Not the First Attempt

Swiss banks are well-acquainted with this hurdle. With Switzerland's access to the single market on hold over a vote to cap immigration, the alpine nation has attempted to strike bilateral deals with individual countries instead – a tedious and long-winded process.

Switzerland's bilateral attempts are likely to get more attention if the U.K. is adopting a similar approach. Switzerland's lobby already made an attempt at a so-called F4 alliance in 2012 with London, Hong Kong, and Singapore, but little came of it.

«It's a good time to broach the idea again,» the lobby spokeswoman said. The goal is to better coordinate the world's finance centers not just for market access but also for regulatory and tax matters.