Bank of America is being accused of misleading some of its Merrill Lynch brokers after introducing changes to its international dealings that a lawsuit alleges “devastated” the brokers’ businesses and relationships with clients.

Lawyers for three former Merrill brokers - part of the so-called Thundering Herd, who worked in the US but focused on clients in foreign countries - said the brokers were "significantly hindered" by changes introduced by the bank in July 2015. Those changes included slashing the number of countries in which the bank could target clients and curtailing the brokers' ability to travel outside the US.