The family of property tycoon Nicholas Hoogstraten is suing Barclays bank alleging it held on to almost £500,000 of his money.

Hamilton Property Holdings Ltd (HPH), the company run by Mr Hoogstraten, his son Rhett Hamilton and others, says it "lost" $900,000 for four weeks following an attempted transfer from Barclays in Mayfair, London, to a Swiss bank account in Luxembourg.

HPH is now planning a lawsuit against Barclays.

Rhett Hamilton, HPH's financial director, said the money was meant to have been sent on January 22 and received on the same day.

It is claimed the money was debited from HPH's account on January 25 but by February 15, Mr Hamilton's client had still not received it.

Barclays then told Mr Hamilton a "Swiftbic" money transfer code was needed to complete the transaction, which HPH argued was not needed for a transfer of US dollars within Europe.

It set in motion a complex series of disagreements between the bank and HPH.

The Hoogstraten family company claims to have been blocked at every attempt to retrieve its money. Mr Hamilton said he later found the money had been put back into HPH's Barclays account.

The bank has rejected the company's account of the dealings saying it was inaccurate.

HPH is now considering a legal claim against the bank for loss of interest and losses it says it made on the dollar-pound sterling exchange rate.

Its statement said: "Mr Hamilton, Hamilton Property Holdings and other family companies are now proposing to move their extensive banking requirements elsewhere and being no stranger to the courtroom will launch aggressive litigation against Barclays."

Mr Hoogstraten's UK base is at the Courtlands Hotel in Hove.

The tycoon was convicted of the manslaughter of Mohammed Raja, a former business associate, who was shot dead on his doorstep in south London in 1999. He was cleared by the Court of Appeal in 2003.