By Huw Jones LONDON (Reuters) – Forcing foreign bank branches in the European Union to become subsidiaries would be a “last resort” to shed light on regulatory blind spots, a senior EU official said on Tuesday. The bloc has proposed tightening up how foreign banks from Switzerland, Britain, Japan, the United States and elsewhere can offer wholesale market services to customers in the EU. The proposals follow Brexit, which saw UK banks setting up branches in the bloc, and have rung alarm bells at some foreign banks, Reuters reported last month. Many foreign lenders currently offer wholesale ser…