As U.K. Prime Minister Theresa May begins the Brexit process on Wednesday, the country's financial center in London, known as the City, will likely face a slow hemorrhaging of its business, analysts said.
Wednesday marks the point of no return for May as the critical step to notify the European Council that the U.K. will officially terminate its 44-year old membership. The move follows a referendum on June 23 last year that rocked the country's political establishment with a narrow win in favor of leaving and led to the resignation of David Cameron as prime minister.
For the financial center in London, that could signal a slow steam toward the exit as banks based there could lose "passporting" rights, or the ability to provide services to the rest of Europe.
"You cannot drop your membership in the country club and still enjoy all the benefits with it," Horst Geicke, chairman of the European Chamber of Commerce in Hong Kong, told CNBC's "Squawk Box" on Wednesday.