Siccar Point Energy, a company backed by Blackstone, the US private equity group, has agreed to pay up to $1 billion for the North Sea assets of Austria's OMV.

It marks the biggest acquisition in the UK offshore energy industry since crude prices crashed two years ago and highlights the interest of private equity investors in the North Sea as cash-strapped oil companies shed assets.

For Aberdeen-based Siccar, the deal seals its arrival as a serious player in the North Sea with stakes in three of the biggest new UK oilfields alongside partners including BP, Chevron and Statoil.

For Vienna-based OMV, the disposal supports efforts to streamline its business in the face of weak oil prices and refocus on lower-cost regions such as the Middle East, Africa and Russia.

Reduce presence

OMV is the latest of several energy companies to exit or reduce their presence in the North Sea – one of the world’s oldest and highest-cost offshore oil basins.

However, Mustafa Siddiqui, who heads Blackstone's energy activities in Europe, said there was still value to be found in UK waters.

"The death knell for North Sea oil and gas has not yet rung," he told the Financial Times. "There are parties like us who want to invest in the basin and find new oil but we have to be selective."

The OMV disposal includes 11.8 per cent of the Schiehallion oilfield, which is due to come back on stream soon after redevelopment by BP and Royal Dutch Shell, and a 20 per cent stake in the Rosebank field, which is awaiting development by Chevron.

These assets will add to the 8.9 per cent stake in the Mariner field, operated by Statoil and due to start production next year, which Siccar bought from JX Nippon of Japan in August.