Achilleas Kallakis, received a sentence of 7 years and his co-conspiritor Alex Williams received a sentence of five years.
Kallakis is thought to have tricked a series of bankers into believing he was a super-rich Mayfair property baron convincing them to lend him millions to fund lucrative deals.
The men previously stood together at the same court 18 years ago after pleading guilty to a forgery scheme involving the sale of bogus manorial titles to Americans.
The men had since changed their names which is why it was not picked up by banks.
Kallakis and his close friends had to deploy actors, offshore trusts and create fictional backing from an overseas shipping empire using a string of bogus references to avoid suspicion.
The Allied Irish Bank was reported as being the biggest hit which had advanced in excess of £700m and ultimately reported a £56m loss on the deals.
A second count was tied to a loan from Bank of Scotland, now part of Lloyds Banking Group.
