The bank came forward as part of a voluntary programme launched in 2013, which allows Swiss banks to admit their potential role in helping US account holders conceal assets to avoid their taxes.

EFG held a total of 919 US-related accounts since 2008 with a peak value of approximately $1.58bn, the DOJ said.

EFG bankers made at least 72 business trips to the US, and in at least one case communicated with clients and lawyers via fax rather than email to avoid their communications being intercepted by the US authorities.

Upon the closure of accounts it also transferred hundreds of millions of dollars to other jurisdictions, including Bermuda, Guernsey, Liechtenstein, Monaco, Luxembourg and Hong Kong. The total funds transferred were above $12m to each country.

Caroline Ciraolo, acting assistant attorney general at the DOJ’s Tax Division, said the agreement makes clear that the DOJ’s “focus extends well beyond Switzerland”.

“To those who fled Swiss accounts to hide in other foreign financial institutions – we are right on your trail,” she said.

As part of the non-prosecution agreement, the bank must cooperate fully with the subsequent investigation, provide detailed information regarding accounts linked to US taxpayers, agree to close the accounts of clients who do not comply with US reporting obligations and pay the appropriate penalty.

Deutsche Bank Swiss also recently paid a penalty of £31m to the DOJ after coming forward in its Swiss Bank Programme.

Richard Weber, chief of the Internal Revenue Service’s criminal investigation division, added the information collected through the Swiss Bank Programme is uncovering more non-compliant banks, facilitators and account holders.

“Non-compliant account holders who believe their funds are still well hidden will find that simply is not true. With each agreement signed, the probability that these criminals will be found grows even more certain. We will vigorously pursue those who hide offshore accounts and those who aided this illegal activity,” he said.