Property groups Treasury Holdings and Quinlan Private are on the verge of announcing a €300 million joint venture in waste management.

It is understood that Quinlan Private, led by financier Mr Derek Quinlan, is set to invest just under €100 million in Herhof, the German waste management company that Treasury bought last year.

Herhof needs €300 million in equity and debt to fund the construction of waste treatment plants in Germany, Belgium and Britain.

Quinlan will take 25-30 per cent of this in equity and arrange a loan to cover the outstanding amount.

Market sources said yesterday that the two companies would shortly make an announcement about the joint deal.

Treasury originally sought the investment from European businesses already operating in the sector, but Quinlan approached the company and the pair opened talks. Both Irish companies were attracted by the fact that Herhof is one of just two operators in waste management that offers an alternative to landfill and incineration.

The EU has effectively ruled out continued use of landfill, while there is growing political opposition to incineration.

Herhof uses a system called mechanical biological treatment (MBT) to separate household wastes into recyclable materials.

A patented by-product of the process can be used to replace fossil fuels.

Separately, Quinlan, which earlier this year paid just over €1 billion for the Savoy Hotels group in London, is close to buying a US property portfolio worth $880 million (€663 million).

It and US property firm Golub, with which it has already completed deals in eastern Europe, are completing due diligence on Prime Group Reality Trust, which owns high-profile properties in Chicago.