Achilleas Kallakis, London’s leading property tycoon, was accused yesterday with a £61 million mortgage fraud against Allied Irish Bank and Bank of Scotland.

Before claims of forgery and false representation surfaced, Mr. Kallakis, formerly Stefanos Kollakis, spent an estimated £1 billion on hot properties in London during the boom. He appeared at City of London Magistrates’ Court accused of offences that allegedly resulted in a £56 million loss to Allied Irish and a £5 million loss to the Bank of Scotland.

Mr. Kallakis and his business partner Alexander Williams, formerly Martin Lewis, face charges of conspiracy to defraud, forgery, fraud by false representation, money laundering and obtaining a money transfer by deception.

Mr. Kallakis had earlier been involved in several small-scale unsuccessful businesses, which had few assets. In spite of failures, he was able to reinvent himself as a leading player in London real estate for much of the past decade, striking deals with Telegraph owners, the Barclay brothers, real-estate specialists, the Tchenguiz brothers, and property entrepreneurs, the Reuben brothers.

The £56 million fraud related to losses on property loans made by Allied Irish to Mr. Kallakis’s property group between 2003 and 2007 on a portfolio of assets.

The charges come after a Serious Fraud Office investigation. Both men are on bail awaiting a hearing at Southwark Crown Court in May.