Vincent Tchenguiz, the property tycoon, saw the holding companies behind his largest property business collapse into administration yester-day.

Vincent Tchenguiz, the property tycoon, saw the holding companies behind his largest property business collapse into administration yester-day. Zolfo Cooper, the restructuring firm, has been hired as administrator for four companies within the Peverel Group, which is the UK's largest property management company.

The administration is not thought to be connected to the arrest of Mr Tchenguiz and his brother Robert last week by the Serious Fraud Office, which is investigating the collapse of the Icelandic bank Kaupthing in 2008. The Tchenguiz brothers were two of the City most high-profile entrepreneurs before the credit crunch hit their business interests, which ranged from owning firms in their own right to stakes in companies across the retail, pub and property worlds.

Their spending spree was often funded with cheap loans provided by failed Icelandic banks.

The board of Peverel, including Vincent Tchenguiz, appointed Zolfo Cooper after it was unable to repay debts of £125m.

The directors and Peverel's main lender, Bank of America, had failed to reach an agreement after months of negotiations. Peverel oversees the management of 190,000 residential units in the market for retirement and non-retirement property.

However, Zolfo Cooper stressed that the administration would have no impact on the operating companies of Peverel, which means that its primarily elderly tenants will not notice any change today.

Furthermore, it is understood that the Tchenguiz brothers have kept the freeholds on all 283,966 residential properties they own.

Simon Appell, a partner at Zolfo Cooper, said: "While the business [Peverel] itself was profitable at an operating level, the level of debt in the holding companies was unsustainable. The administrations of the holding companies were therefore unavoidable." He added: "The business will continue to trade as usual while we seek a buyer for it."

The four holding companies in administration are: Peverel, Peverel Group, Aztec Opco Developments and Aztec Acquisitons.

There are no plans to make any of Peverel's 4,000 employees redundant. A Zolfo Cooper spokesman said: "Employees will continue to be paid as normal, and other benefits will accrue as normal."

In a separate development yesterday, Robert Tchenguiz has threatened to sue the Serious Fraud Office for arresting him as part of their inquiry into Kaupthing.

He accused the fraud watchdog's investigators of ignoring his offers to co-operate before he and his brother were arrested last week at the headquarters of their London offices. In a statement, he said the investigations were a publicity stunt for the SFO to show its mettle.

Robert Tchenguiz said: "I believe that the disproportionate and aggressive conduct of the SFO was designed to generate maximum publicity for its own ends, given its uncertain future."