More scientific proof is needed to determine whether the proposed MTRC South Island Line is going to be a sustainable transport decision, Secretary for the Environment, Transport & Works Sarah Liao says.

Responding to enquiries on the economic viability of the proposed railway today, Dr Liao said the Government has always been careful in evaluating what is feasible and cost-effective for the community at large.

She revealed the Government has questions regarding the information provided by the MTRC on the patronage and economic viability of the proposed rail line.

To avoid burdening both the society and the Government, further, detailed studies are required to examine the proposed railway from the perspective of timing and cost.