More than 120 million shares of the stock were traded, the most in any single day in the firm's history.

Hopewell was one of the worst performers on the Hang Seng Index last year, amid reports of huge cost overruns on the highway development and start-up problems at the group's Philippine power plants.

Investors worried that the company, short of funds, would be unable complete other projects, which include more roads in southern China and road and rail projects in Thailand.

It is now reported that the company will form a new subsidiary, which will take in these unfinished projects and 800 million shares of Hopewell affiliate Consolidated Electric Power Asia (Cepa), which builds and operates power plants.

Hopewell plans to sell 25 per cent of this subsidiary - to be called Consolidated Real Estate and Transportation Asia (Cresta) - to investors for $9 billion.

Such a share sale would help to alleviate Hopewell's cash shortage, which some analysts estimate at about $7.2 billion this year.

There has been no formal announcement as to the make-up of Cresta.

The profit share agreement reached with the Guangdong government this week included an injection of 2.48 billion yuan (about HK$2.3 billion) into the Guangzhou-Shenzhen-Zhuhai Superhighway Co.

However, attached to the agreement is an indemnity term that analysts expect to cost the group $1.3 billion in four to five years.

Hopewell has also won concessions to carry out substantial property development along the highway. It has 17.22 million sq ft of land, at various sites along the highway.

They are mostly at interchanges and could be developed for residential, office and retail use.

Michael Green, executive director at the Nomura Research Institute, said this would be enough to develop a total gross floor area of possibly 170 million sq ft of space, assuming a typical average plot ratio of about 10.

The cost of developing these sites is estimated at about six billion yuan for the developer.

Where this start-up money would come from for cash-starved Hopewell seemed to be a mystery to industry analysts.

Mr Green predicted that profit margins would be low, as there was no shortage of land in Guangzhou and Shenzhen. Hopewell sites were also in peripheral areas.

With Hopewell's move to elevate the superhighway and enlarge nine interchanges, there are also about 13.9 million sq ft of shop space along and underneath the highway, as well as 7.3 million sq ft of interchange commercial centres.

Phase one of the superhighway incurred 6 billion yuan in cost overrun for Hopewell. About 2.48 billion yuan of this will now be transferred from Hopewell's subsidiary, Hopewell China Development (Superhighway), to the highway development joint-venture company with the Guangdong government as additional shareholders' loans.

With Hopewell's stake in the highway rising from $2.9 billion to $4.8 billion, analysts calculated that its net asset value per share would have increased from 27 cents to 44 cents a share.