Foreign-exchange trading firm FXCM agreed to pay fines and refunds totalling almost £10 million to settle allegations by a UK financial regulator that the company withheld profits from clients and failed to inform British authorities that it was under investigation in the US.

The Financial Conduct Authority said that UK units of FXCM withheld £6 million from customers on foreign-exchange transactions between August 2006 and December 2010. The regulator said that the broker pocketed profits when exchange rates moved in its customers' favor while a trade was in process, but it passed on losses that occurred on other trades.