'A site has been reserved for a mega terminus even though plans for it have not been finalised yet.'

Under the government's 2000 rail strategy blueprint, the regional express line - designed to reduce travel time between Hong Kong and Guangzhou from 90 minutes to less than an hour - was to be developed along KCRC's congested East Rail track and terminate at Hunghom station, at a cost of $13 billion to $17 billion.

However, disappointing passenger numbers along the KCRC's new West Rail, linking Tuen Mun in the northwest New Territories to Nam Cheong station in Shamshuipo, have caused the government to rethink its original strategy.

The Environment, Transport and Works Bureau, headed by Sarah Liao Sau-tung, now favours building a rail bypass for the regional express line between the Lok Ma Chau border checkpoint and Kam Sheung Road station, where it can continue along the West Rail to West Kowloon.

'The West Kowloon option will minimise new investment by leveraging West Rail assets and eliminate the hassle of building a new rail track along the already developed East Rail,' the source said.

Sources close to the project said the central government had recently sent a directive to Guangzhou and Shenzhen officials involved in the rail link's planning, informing them that it should end in West Kowloon.

However, mainland officials have further complicated discussions by again raising the possibility of using magnetic levitation (maglev) technology for the regional express line.

This strategy had been shelved given the expense and limited proven experience of the technology.

'The Hong Kong government has been avoiding the maglev proposal,' another source said. 'It would be so expensive that it can't see the prospect of the project ever making money.'

Uncertainty over the West Kowloon cultural district, whose single-developer tender has sparked a political firestorm, and a pending merger of KCRC with MTR Corp are also hanging over the regional express link.

Others have expressed concern over the new West Rail routing for the regional express line.

'We already have two MTR rail lines in West Kowloon - the Tung Chung line and Airport Express - and also the KCRC's West Rail line and the Kowloon Southern rail link project,' said Henry Chan Man-yu, chairman of the Yau Tsim Mong District Council.

'But MTR and KCR stations in West Kowloon are not interconnected.'

'The government should be looking at how to better link up existing networks rather than building a new line to rescue another,' Mr Chan said.

'West Rail's [current] Nam Cheong terminus is a joke.

'It is bigger than Central MTR station even though it basically serves the Nam Cheong public housing estate, where 70 per cent of residents are on welfare.'