A bank official from Kent admitted defrauding his bosses of £2 million.
Michael Corrigan, 48, pleaded guilty at the Old Bailey to four offences of fraud committed between January and September 2010.
Corrigan, of Hayne Road , Beckenham, was remanded on bail to be sentenced on September 7.
The charges state that he provided false bank guarantees in large sums of euros, dollars and sterling for third parties.
Corrigan was the risk and compliance director for Nigerian-owned Access Bank in the City of London .