LONDON (Reuters) - HSBC Holdings said Britain's regulator was the only authority it was holding "detailed" settlement discussions with over allegations of the manipulation of currency markets. HSBC made a $378 million provision on Monday for possible settlements over alleged foreign exchange market rigging, and it said all of that was to cover a potential fine from Britain's Financial Conduct Authority. "At the moment the only detailed settlement discussions in which we are involved is with the FCA," said Iain Mackay, HSBC finance director. "There are a number of other jurisdictions that have expressed interest in this topic and we are working closely with authorities in each of those to work through those issues," he said. (Reporting by Steve Slater; Editing by Matt Scuffham)