A lawmaker on Sunday questioned whether Hong Kong has become too reliant on the MTR, as he and one of his colleagues urged the rail operator to step up maintenance and risk management work.

They made the comments on a radio programme a week after a partial train derailment at Yau Ma Tei Station forced the closure of a stretch of the Tsuen Wan Line for most of the day.

"The role of the government of course is to ensure the MTR operates smoothly and also other transport facilities can sustain [public transport]. If our transport merely relies on the MTR, when the MTR has any problems, the other transport cannot support people's needs. So, should we review the policy of merely relying on the MTR?" said Ben Chan, the chairman of Legco's railways subcommittee.

He said the incident highlighted a need to expand other transportation networks, noting the major traffic congestion on Nathan Road on the day of the Yau Ma Tei derailment.

The MTR Corporation said last Sunday's incident was probably caused by the train striking a displaced metal barrier.

Speaking on the same Commercial Radio programme, another lawmaker and former MTR engineer Gary Zhang said reviewing the MTR's maintenance regime should be a key focus of the full investigation.

"It's worth some effort to look into the current arrangement, especially regarding those permanent fixtures in the tunnels, like the metal barriers, because according to past practices and industry standards, these permanent fixtures do not require a lot of frequent inspections or preventive maintenance. But from this incident, it is obviously a lesson learned that we need to have a rethink about it and to really improve the current maintenance guidelines," he said.

Zhang said the railway corporation should also find out if the accident was in any way connected to a shortage of maintenance staff.

"In the investigation report, we also need to look at whether a lack of manpower of the maintenance and operating department have some contributory effect to this incident," he said.