A government official said while authorities did expect most passengers on the link to stop in Shenzhen initially, an increasing number would eventually stop at Guangzhou, and more would take longer-haul trips to cities such as Beijing and Wuhan , which now takes about 10 hours.

However, the report indicated the opposite. Only 25 pairs of trains, or 17.85 per cent of the 140 train pairs to run by 2030 - 15 years after the link begins operating - will stop in Guangzhou, while 108 pairs of trains, or 77 per cent, are still expected to stop at the two Shenzhen stations.

The latest revelation has raised doubts about the effectiveness of the project, which a concern group said had been reduced from a national rail link to a domestic shuttle train.

'Why would 70,000 passengers want to take the much more expensive high-speed rail link to Shenzhen every day, while they now have coaches, ferries and at least two cross-border railways, all much cheaper means, that serve the same purpose?' said Chu Hoi-dick, an activist of Local Action, which has been helping villagers of Tsoi Yuen Tsuen, who have to make way for the link.

The Transport and Housing Bureau projected in April that a total of 99,000 passengers would use the link every day in 2016, including 88,000 who travel within Guangzhou and 11,000 who switch to the national rail network.

Authorities have not yet set fares for the link, but it is widely believed they will be higher than the current MTR through train service, which costs HK$190 per trip. Increasing construction costs of most major infrastructure these days mean the express link may end up costing much more than its original budget of HK$39.5 billion, and possibly leading to higher fares.

Chu said if the distribution of passengers was expected to match that of the arrangement of trains, then around 80 per cent, or 70,000 of those expected to travel within Guangzhou were actually going to Shenzhen.

As of June, a daily average of 6,607 passengers took the MTR's Hung Hom-Guangzhou through train to cross the border. A further 278,960 crossed the border on the city's two cross-boundary rail lines at Lo Wu and Lok Ma Chau.

In response to the report's projection, the government official said the figures were more an illustration of passenger demand than a final train schedule.

'Everything depends on the actual passenger demand when the link opens. Many of the trains now thought to terminate at Shenzhen, may actually only stop there as a middle station, and then move on to Guangzhou.'

But the official admitted engineers always minimised stops for a high-speed network.

The latest finding will almost certainly raise more controversy at a Legislative Council panel meeting tomorrow, during which officials are expected to be asked about a compensation plan for villagers who will have to move because of the rail.

Some may also raise questions about the link's terminus at Shibi. Although it will take only 48 minutes to get there from Hong Kong, passengers heading to Guangzhou city centre at Tianhe will have to transfer to the Guangzhou metro and ride another 18 stops. This will take about 45 minutes, which means there will not be much of a time saving in comparison with the through train.

The Transport and Housing Bureau said the new Guangzhou station, although now located on the city's outskirts, would become the largest passenger railway station in Asia when it started operating early next year. It also connects to more than 10 high-speed national railways, highways, urban metro lines and inter-city links.