Tycoons from across the world are bidding to build a £4.2bn “super-sewer” that will travel under the heart of London.
The Thames Tideway tunnel, which will be 12.5 miles long and wide enough to accommodate three double-decker buses, is considered to be one of the UK's biggest infrastructure projects.
The project will funded partly by Thames Water and partly by a government guarantee, and the construction will be overseen by a new independent investment vehicle.
Bidders have been invited by UBS, which is running the auction, to compete for control of this investment vehicle. At least four consortiums have successfully made it through the pre-qualification step.
Among those competing for the right to build it are the richest man in Hong Kong and the rulers of Abu Dhabi, according to The Sunday Times.
Li Ka-shing is expected to make an offer through his holding company CKI. Other retail chains owned by the Hong Kong billionaire include Superdrug and London's electricity network.
Abu Dhabi's sovereign wealth fund has teamed up with Canadian pension Fund CPP and British private equity firm 3i to make a bid.
The purpose of the sewer is to stop raw sewage overflowing into the Thames, but the plan has proved divisive with many claiming that it will be too disruptive. Critics include local councils and residents who live close to the site.
The auction is expected to take nine months to complete.