Barclays has reached a $298m settlement agreement with the US Justice Department and the New York County District Attorney's Office in relation to accusations that it has facilitated financial payments in countries facing US sanctions.
The probe relates to transactions worth $500m undertaken between March 1995 and September 2006 by Barclays in Cuba, Iran, Libya, Myanmar and Sudan.
During the period Barclays allegedly hid the origin of the countries by removing details of payments.
Barclays is understood to have voluntarily disclosed information on the dealings to the authorities after it became aware it might have broken sanctions.
Barclays is not the only bank in the UK to have been fined for violating US sanctions. In January 2009 Lloyds TSB was fined $350m after being accused of helping clients in Iran, Libya and Sudan avoid US sanctions.
In December 2009, Credit Suisse was asked to pay $538m for hiding several thousand transactions in Iran, Libya and Sudan. This March Wachovia paid $160m to settle charges that it had failed to prevent more than $100m being laundered by Colombian and Mexican drug gangs.