Exclusive: U.S. regulators query banks on their 'Brexit' contingency plans - sources

By Anjuli Davies and Rachel Armstrong LONDON (Reuters) - U.S. financial regulators are demanding regular updates from Wall Street banks about their contingency plans should Britain vote to leave the European Union, banking and regulatory sources told Reuters. Scenarios under scrutiny range from how their London operations would handle lengthy uncertainty if Britons opt to quit the bloc in a June 23 referendum, to whether they could still offer financial services in continental Europe from a non-