This is not the first deal in the UK by Blackstone. Earlier in the year it sold the Savoy Group of hotels and bought NHP rival Southern Cross.

The UK company is one of the largest owners of private care beds in Britain, with 355 care homes and 17,400 beds. Originally it was a property business specializing in sale-leasebacks of care (nursing) homes with mom-and-pop operators. But changes in the way government-funded care homes meant many operators struggled to pay their rents, and NHP was forced to become an operator in its own right. Bill Colvin, chief executive of NHP, is to stay on for a few months to help Blackstone integrate its new business with Southern Cross.

Analysts suggest that NHP's operating company, Highfield Care, fits well with Southern Cross, which is also one of NHP's biggest tenants. They also suggest that the care sector is well placed for further consolidation and attribute the increased venture-capital interest in the nursing-home sector to the rising cost of building new care homes under the new care standards.

Colvin says that venture capitalists were expecting the fees paid per patient by local authorities to rise partly because it costs more to keep the elderly and infirm in a hospital. "Care homes are as good a method as any to look after people. There is always a demand and they are a cost-effective way to provide care.

"Fee levels have got to rise significantly," he adds. "The venture capitalists are taking that chance that fees are going to go higher. There has been an above-inflation increase this year, but there will need to be more."