Lawyers from Linklaters' New York office have worked alongside Sullivan & Cromwell to advise Lloyds TSB on a $350m (£230m) settlement with the US government.
The UK bank allegedly falsified records to allow transactions from banks in Sudan and Iran appear as if they originated from Lloyds. In the US certain countries are forbidden from accessing the banking system.
Lloyds admitted that it falsified business records by altering wire transfer information to hide the identity of its clients, and agreed to pay $350m to settle investigations.
Linklaters US co-managing partner Larry Byrne and New York-based partner Jo Armao worked with co-counsel Sullivan & Cromwell partner Sam Seymour to advise Lloyds.
Lloyds was investigated by Manhattan district attorney Robert Morganthau of the US justice department.
Barclays and Credit Suisse have also come under fire in recent months for violating US banking sanctions. Investigations into these two banks is ongoing.
Linklaters and Sullivan & Cromwell declined to comment.