The National Asset Management Agency has taken control of a London hotel owned by developers Ray and Danny Grehan ahead of a court application in the UK next week to strengthen its security on loans of €650 million.

The State loans agency appointed accountants from the UK office of Grant Thornton to the Crowne Plaza hotel in Shoreditch in the east of the city today.

"Nama felt it was necessary to take direct action to protect its security," said a spokesman for the agency.

Statutory receivers, Michael McAteer and Paul McCann of Grant Thornton, were re-appointed to the Grehans' Irish company, Glenkerrin, and property assets last Tuesday evening. The appointment was made after the Grehans failed to meet a demand from Nama for the repayment of the €650 million debt.

Nama will make an application to a London court on Tuesday to improve the quality of the agency's security over the UK assets of Glenkerrin and the Grehans.

The agency will ask the court to appoint an administrator to assets owned by the company and the brothers in what will be the first such move by Nama in the UK.

The UK accounts for about half of the Grehans' business where they have rental income of about €11 million. The company has an undeveloped site in Canary Wharf and a shopping development in Ealing Broadway in west London.

In an unusual move, Nama asked the statutory receivers it had appointed to Glenkerrin and the Grehans' property assets late last month to stand down two days later after receiving legal advice.

Control of the properties were returned to Glenkerrin and the Grehans last Saturday morning before Nama re-appointed the receivers last Tuesday evening following the repayment demand.